Gotta say Duck, you have some large nuts!
We have a somewhat similar upright holder with a screw-on top nut and a side mounted dowel to keep the roll from unspooling.
I hate the thing, mainly because I'm always the one who has to refill it. The screw top takes about 30 turns to spin off and the dowel always makes the first 30' or so impossible to pull off without snagging and tearing the paper into tiny pieces. Would anyone tolerate that with bog paper I ask? Noooo!
Need to make a proper one, bearing base, short one turn top , and no frickin' dowel!