I was going to pick up some of these when I order a CV joint removal tool:
http://www.cip1.ca/ProductDetails.asp?Prod...2D501%2D229%2DD

They're 8x48mm with a hex socket instead of 12 point. Is that the right size to fit the 914?

Dude;

Take a look at Dr. Evil's CV bolts. They're not expensive and they are drilled and supplied with wire to ensure they do not back out. He's in the "Member Vendor" forum (no affiliation).

the size is the same, but get the 12 point. hex heads strip out way too easy.

VW part # is an 893-407-237 and they run about $2 a piece from VW

you can get the triple square sockets for about $8 at NAPA

best option is to get Dr. Evil's super CV bolt kit though