ID add these three to your supplier list...
http://www.dougherbert.com/
http://www.summitracing.com/
http://www.jegs.com/webapp/wcs/stores/servlet/topcategory_10001_10002_-1
btw all three above YOU LISTED are fine, but you (need to know what parts your ordering, a good deal of the parts handled by
1) Corvette America.
2) Eckler's.
3) Mid America.
are just fine and the serivice is great, I deal mostly with #3, but never had a problem with any of there service.....some parts are cheap crap that should never be sold thou.....example
http://www.madvet.com/shop?frame=1.1019
total crap that shriveled up like a burn potato chip in the sun after 30 days)
http://www.dougherbert.com/
http://www.summitracing.com/
http://www.jegs.com/webapp/wcs/stores/servlet/topcategory_10001_10002_-1
the three suppliers above can supply many parts that the corvette specific guys don,t handle