3/4” piece of copper tubing, sharpen it with a rat tail file. Then you can cut them out of the styrofoam foam trays that your meat comes on from a grocery store. Cheap and easy!
Went down this road years ago, finally found what works. I sold the TK and bought a MK-86. Uses REM chokes and opens up a whole new world of patterns for you. I know this isn’t the answer you were looking for, and the MK 86 recoils a lot less than the TK.
Here is a link
https://patmarlins.com
He used to sell a pocket luber that lubed 4 bullets at a time.
This works great but I think he stopped making them.
Most people never realize that the are 2 tiny grey glands under the front arm pits, if you don’t remove those, they will taste gamey no matter what you do.
Awesome fish and stream pics. Love fishing Tenkara, in fact I fish it more than I do my regular fly rods. Works great on our streams in NJ and PA. Where are you located?
I have owned 4 different knight 54 cal. Over the years and all of them shot lights out with Barnes 325 grn. bullets, purple sabots with 90 grn. Of any powder I put thru them.