Hi hayduke,
I'm in a similar boat. When I looked into selling mine on eBay a couple of months ago there was very little action on the iMacs with logic board issues. A quick check today showed a couple of iMacs being sold for parts but again, little interest (so far, anyway).
Just wondering if you've been following the auctions and what sort of price you think you can get. I think I'm out of luck with mine because I'm actually in worse shape than you. Not only are the capacitors shot but the logic board itself is damaged and therefore unrecyclable. At the places I've been to, the $450 repair is for capacitor replacement, and contingent upon being able to recycle your board. For a repair with a new board, the price is around $950.
Whichever way you go, I hope things go well.