Could give loosescrews.com a try. (http://www.loosescrews.com/ )
Hmmm. Or maybe... http://www.oldroads.com/ .

Have no idea, but they're good places to start.

Could also do a QBP search with one of the big online indie stores (harris cyclery as an example.)

But brokenrobot's right, if they're just the cable/cable housing stops, then you can go ask at your LBS--they'd probably just give you a couple for free--or they also come with housing/cable sets, about $7 at the LBS.