Dood, if you were local, and I hadn't already bought my rims and tires about 2 months ago, I'd be ALLLL over your deal.
I got 17" rims and tires for a sweet deal: $400 - but I had to put on two new tires, the other two were good - so my total ended up being about $650 - which actually wasn't too bad because I blew a tire about 2 weeks down the road and it was covered by America's Tires policy for free hoo hoo.
Of course, 18" would be so sweet.
I've been stupid a few times too, where I complained that prices were too high, but I apologized once I learned they weren't,

. Sometimes prices are too high, but yours are in no way too high, unless you banged up those rims drifting, hahaha.
You should have no problem selling those for $650. Just post ad on more or different forums or something.
I know that FreshAlloy.com and Zilvia.net have pretty good people on there. I've bought stuff from guys on those boards before. People are nice.