I sold my RK's for 3k, 550 a set is a steal lol. Who knows if the offset would work, and the fact you are stuck with 18x8 on all four corners which is lame IMHO.
The camry rk's are a little bit different. Spokes aren't as straight and they don't have any dish since they are FWD offset. Probably require a set of spacers. For that cheap though I say go for it!
Around 2010 I called BBS about ordering valve stems, since if you used anything other than BBS they would slowly leak air. The gentleman I spoke to said they were going to put this wheel back into production for the Mustang. Have yet to see it unfortunately.