http://www.vpartsinc.com/
This is the website for the company that the dealers go to to find parts no longer available in the inventory. Save it to your favorites. I just had a ZR-1 owner here order the triangle piece for the sport seat adjustment there.
They buy inventory from manufacturer's when they are done carrying the parts. Check them before you look on Ebay for anything. You need the part number.
Examples:
Triangle Piece
http://www.vpartsinc.com/search?manu..._with&x=11&y=8
Radiator Inlet Hose, Eng to Tee (Need 2)
http://www.vpartsinc.com/search?manu...with&x=18&y=10
Thermostat to Radiator Hose
http://www.vpartsinc.com/search?manu..._with&x=11&y=6
They have a lot more too, just check them. Have fun.