Rod Richeson wrote:

I've checked the usually suspects, Little Machine Shop, Horrible
Fright, Enco, for a 0.25" R8 mill end holder for my mini-mill. I have
2 items I want to buy individuals holders for and they are both 0.25".

You can get them. I got two Collis EM holders from MSC, I think. After
searching
all over, I ended up paying $45 apiece for them, on sale! I really
don't know any solution
other than buying it at full price, unfortunately. I don't know why
this one particular
size is so hard to come by.

Jon