I have number 3, 7 some of 14, one of 16, and 20.   The others on this short list can be found on Ebay quite often.   One seller sells the Gunstar, the Winnebago, and Moya on a regular basis.  They use to sell the Huey, Duey and Louie robots as well.  

The others on this short list I have seen on Ebay from time to time.   Fantastic plastic sells 25.   I recently saw a lot of number 16 somewhere, but don't remember where.

Most of these are resin kits, so they can be a bit expensive....