The following illustrates what I was trying to do:
property MyList : {A1:"Foo", A2:"Bar"}
choose from list {1, 2}
set myPick to "A" & result
get myPick of MyList
--> Can't get myPick of {A1:"Foo", A2:"Bar"}
The problem is that I don’t know how to (or whether I can) turn myPick (which is text) into a suitable reference for getting a piece from myList.