I have a part being machined that calls for 2 captive studs to be
inserted and thought I'd try to put the studs in myself. They're
stainless, 8/32 about an inch long and require a .163 pocket
(partially drilled hole).

I thought that maybe I could build some sort of jig to keep them
straight and then tap them with a hammer?

OR--

Is there a small accessory or something that maybe I could use with an
arbor or vise? Any ideas?

Need to do them myself to save some time and money.