Openbuilds Lead Screws.

I bought an 8mm lead screw on amazon and found out the openbuilds lead screws are actually 7.8mm in diameter not 8.0mm. Anyway, the openbuilds part store is out of the 500mm length. Can someone tell me if there is another source for these?

I was bummed that the 8mm lead screw that I bought wouldn't fit in the bearings or the openbuilds flexible coupling. I'm sure they could be pressed on but that would be a pain...

-Eric