You can buy an almost perfect one for under $10K, and couldn't even think about restoring that one for less. When it comes to Rivieras especially, you're far ahead to pay more for one that is in great shape already rather than trying to fix one up.
I'm putting up my 68 Riv for sale in the classifieds as soon as I get 10 posts, so I can include a pic.
What's really cool is how from the side it looks like a 68 but from the front it looks like a 65. Wicked custom kit, I guess. -- Steve