Hmmm. There are several places you might try - Harry Pellow, aka "The Maestro" has a supscription based sale service. You can reach him at hcpresearch.com
I used
www.classifieds2000.com to buy my 1967 Porsche 912 Targa back in '97. There's also a good site called Highway 1; they have their own cars, but they also list other folks cars. I think the site name is
www.highwayone.com
Good luck!