What does the shaft hole in the squirrel cage look like? If it's completely round, you might have a problem. If it isn't (like having a flat side), then it should be no problem.
Believe it or not, fans are fans. I pulled this one out of one of our VAV boxes in my building last week. Same principal, only a little bigger (about 18" in diameter). A new $78 motor and she'll be good as new, cranking out about 1700 CFM.
Honestly, though, even if it is a completely round hole, roughening up the shaft and applying a little gorilla glue will more than likely do the trick...
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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608
Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.