Want to Buy WTB: 100mm Red or Yellow Filter

I was recently given a few Pentax 67 lenses. Among them is the older 55/3.5. This thing is massive and from what I have read online it takes 100mm filters. Any one have these?

Are you looking for a bayonet mount or a screw mount?

I believe this uses a screw in filter. Even a 100mm-105mm adapter would do I think.

Just to throw in here, the lens does take some pentax bayonet filters but supposedly theyre quite hard to find. I was quite lucky to get a orange filter and UV filter when I bought mine. OFC with these being so hard to find perhaps a screw filter is your best bet