Try
http://www.cobracountry.com/
At any given time there are probably 20-40 cars for sale here. Also check out (under Cars/Parts for sale)
http://www.cmstreetperformance.com/
They have a great Factory Five car for sale; professionally built - only drawback, (for some of us), is that it has an automatic tranny.
These guys did my body/paint and all the suspension work. I'm sure the price on this car is negotiable.
- Dan