What are you looking for, I have a new set from my Farley rest. I bought my new ones from PMA tool.
Model: BFS-1000 I think I paid about $35 for them. I still have the ones I replaced if your interested in the original style.
The ones offered by PMA are the type I'm looking for, I think I've seen some with a larger knurled top. Do you happen to know the diameter of the ones you have? Thanks, JB