Nitrous Al:
Try this link for Muscle Motor Sports in Huntsville, N.C.
http://www.musclemotorparts.com/
Here's a comment from their website:
"We buy our parts direct from the top Winston Cup and Busch teams, many of which are exclusive to Muscle. We inspect , refurbish or rebuild all parts that come through our doors, we do this because we guarantee everything we sell. Many parts are "trick" and cutting edge as far as performance, design and durability are concerned.
Sounds like what you're looking for, or close to it.