.590 is bass bore, you're going to want the .559" bore one even if your tubing is nominally .562.
That said, there are a few older threads with people replacing their Bach 42 rotors with 50 or otherwise bass rotors. I recall someone selling a Shires bell with a Bach 50 rotor as well perhaps in 2014 too. Shires did some experiments with that type of setup and found it made the intonation very quirky (basically quite flat, memory serving).
If you're going to replace the neckpipe portion, consider getting the ones that Brad Close makes. Heard very good things and you might stand a chance at getting it sometime this decade
Also, maybe consider the Olsen valve (the guy who makes the Infinity Thayers). I've not known anyone who has put the rotors on personally but lots of praise here about the Thayers. And they're about half the price of a Rotax.