Just keep looking. You'll find some guy who will sell it for a buck or two eventually. You'll need it cheap because Quadra 900s/950s are a pain to ship.

The number of 68K Macs is shrinking but the demand for different types of machines have gone up and down. For example, the Colour Classic is always in demand, but there aren't as many people interested in SE/30s as there used to be. Quadras are more popular now. Classics have gone up in price but aren't really popular anymore.