The screws are metric thread which might throw some local vendors and just about every Ford dealer I know of. Try places that supply parts for European or Japanese cars and you might have better luck. Another option is to switch over to speed bleeders. There is some debate about using them, but I've been quite happy.
Here is the link to speed bleeders, and the part numbers:
www.speedbleeder.comParts:
SB1428 (1/4 X 28 X 1” LONG) X 1 for the clutch slave
SB8125LL (M8 x 1.25 X 1.5” LONG) x 6 (3 pairs) for callipers
You can get them in stainless (I didn’t) or regular. Also, get the I.V. bag as well, if it’s not included (can’t remember), but it simplifies the one-person bleeding process.
Mark