I bought this set of 6 a while back and used them. Couldn't find them anywhere else, and I think it was about $2/grub screw including shipping.
http://www.ebay.com/itm/161123175217...84.m1423.l2649
I have a few drawers of stuff I haven't mucked through- will check them out in the next few days and get back to you if I find a stowaway.