Think one of those aftermarket knobs would work on this handle from a Fin Nor Marquesa 40 2 speed?
Get one of Alans.
Recently on an old! Daiwa LD30 I managed to get a centred punch mark on the shaft and drill out enough of the peened over shaft/washer to allow me to punch out the shaft to leave a clean(ish) hole for an aftermarket shaft/knob. Costs little to try.
When you're drilling it out, any knob will work.
But I agree with Lee.
Centering the hole perfectly can be hard and I have several centering guides I have made out of scrap 3/8" aluminum.
First drill a small hole in the aluminum, 1/8" drill is what I use. Next measure the OD of the back side of the shaft and get a drill that is the same size or slightly larger and drill part way through the metal making sure the pilot hole is still 1/8" on the back side, I drill 1/2 way through. Measure your centering punch diameter from the tip to whatever the thickness of the aluminum at the bottom of the larger hole and them measure the diameter of the punch there. Drill out the pilot hole either slightly smaller or the same as the punch diameter. Use the punch to shape the hole so it just bairly comes out of the bottom of the larger hole.
I have a 2x4 that has holes in ut for the handle shaft to drop in and I put the punch guide over the rivet and then punch the center hole. Remove guide clamp the handle and 2×4 to my drill press, drill a pilot hole and then drill out the shaft with a larger drill but smaller than the shaft. I use a drill slightly smaller than the shaft and my drill press to press out the shaft. Now you can drill out the hole to match the new handle if needed.
I've posted about this before. I suck at centering anything, though I'd never heard of Lee's method above. But I tend to grind off the "mushroom" (the peened part of the knob shaft) with various methods including starting on my bench grinder and finishing with a Dremel, and then just yanking it out. Knock on wood I've never scratched the handle more than what is covered by the seemingly mandatory washer on the screw side. But I have once ruined a handle trying to drill it out.
I like knobs where the handle and shaft are integral, and require only one screw to replace the drilled out rivet.
Alan's look like they are made that way, as well as some of the offerings from ProChallenger.
Some of Alan's are and some attach to different reel manufactures posts.