I'd go with yamaha Clutch (or tama) . It's not 'always' you run into hole fit troubles. Intermediates hi hats never stuck around here for very long long. They are as hi hats- unusual. Pretty potent on the Ice part of Dry dark Ice...(I presently have 16, 18 and 20 did have a 22 at one time; Intermediates) altho today there isn't anything that sounds comparable from any other maker anywhere..They sounded awesome! The center hole are still small though. Is there a hi hat sleeve they work best with, minus drilling the holes
This is my general approach. If the ink has nothing around it you can soak the solvent in better. But the ink is almost on the signature, so you want to try to use detail work. Chances are the solvent (I've used hairspray, alcohol, and wd-40 and other stuff just look up sharpie removal) will be less effective as JDA stated on the 50 year old signature than the 5-10 year sharpie (if it is even sharpie. It could be a less durable marker ink if you're lucky.)Lots of Q-tips, just a little solvent on each. Be presice, wipe then toss the Q-tip and get another, repeat.
I can agree with JDA & JP, it's part of its story, but it's also defacing part of its history.
If it were mine I would try to clean around, and save the original.
Good luck, let us know how it turns out.