How do I change Unicode text size?

I use the following script to rate my iTunes tracks. As you can see, in addition to changing the track rating, it also displays a rather nice Growl notification diplaying the appropriate track info, using Unicode symbols for the rating stars. The problem: Ever since I upgraded to Tiger, (using 10.4.2 now), the unicode symbol for the “black_stars,” or the active stars representing the 1-5 star rating, have been much smaller than the “white_stars,” or the ones representing the null spaces (i.e. # of white_stars" = 5 - rating (“black_stars”)). So my question is, how can I increase the size of the “black_stars” so that they match the size of the “white_stars”?
Here’s the script for a 4-star rating, with 0-3- and 5-star rating scripts being similar:
(NOTE: These are not my scripts–I don’t remember where I got them, but they’re not mine!)

property black_star : «data utxt2605» as Unicode text
property white_star : «data utxt2606» as Unicode text

tell application "System Events" to set GrowlRunning to ¬
     ((application processes whose (name is equal to "GrowlHelperApp" ¬
          )) count)

if GrowlRunning is greater than or equal to 1 then
     set appName to "iTunes ratings"
     set notificationName to "Ratings"
     set notifs to {notificationName}
     tell application "GrowlHelperApp"
          register as application appName all notifications notifs default notifications notifs icon of application "iTunes"
     end tell
     tell application "iTunes"
          if class of current track is in {track, file track, URL track, device track, shared track, audio CD} then
               set aTrack to current track
               tell aTrack to set rating to 80
               set puppies to (name of aTrack)
               set rate to (rating of aTrack)
               set stars to (rate div 20)
               if rate is greater than 0 and stars is equal to 0 then
                    set stars to 1 -- after all, a 10 rating isn't no stars
               end if
               set giraffes to "" as Unicode text
               repeat with i from 1 to stars
                    set giraffes to giraffes & black_star
               end repeat
               repeat with i from stars to 4
                    set giraffes to giraffes & white_star
               end repeat
               
               if class of aTrack is URL track then
                    set kittens to current stream title
                    set chickens to (bit rate of aTrack)
                    tell application "GrowlHelperApp"
                         notify with name notificationName title "Streaming Radio (" & chickens & " kbps)" application name appName description puppies & return & kittens & return & giraffes
                    end tell
               else
                    set chickens to (album of aTrack)
                    set kittens to (artist of aTrack)
                    if exists artworks of aTrack then
                         set aw to data of (artwork 1 of aTrack)
                         (*
                         tell application "GrowlHelperApp"
                              notify with name notificationName title puppies application name appName description kittens & return & chickens & return & giraffes pictImage aw
                         end tell
                         *)
                         tell application "Quicksilver"
                              show notification puppies ¬
                                   text kittens & return & chickens & return & giraffes ¬
                                   image data aw
                         end tell
                    else
                         tell application "GrowlHelperApp"
                              notify with name notificationName title puppies application name appName description kittens & return & chickens & return & giraffes
                         end tell
                    end if
               end if
          else
               set puppies to "No current track"
               tell application "GrowlHelperApp"
                    notify with name notificationName title puppies description puppies application name appName
               end tell
          end if
     end tell
end if

You can’t change the size of unicode text - there is no concept of font size in unicode text, it’s just a string of characters.

However, the two characters selected do render differently, such that the black star appears smaller than the white star.

The simplest solution I can think of is to change the black star character to a different star that more closely matches the size of the white star. A quick glance at the character palette makes me think that:

property black_star : «data utxt272E» as Unicode text

would work better than:

property black_star : «data utxt2605» as Unicode text