Any good tonearm would do but the constraints on your choices have to do with the effective length and pivot to spindle distance and the specifics of how the OEM tonearm is mounted. None of these parameters are known to anyone but you. Not to say that the new TA needs to be exactly like the original, if you can fashion a new mount.
Pioneer SL-570D TT Tonearm Suggestions
I acquired from the original, now deceased, owner a pristine Pioneer SL-570D TT. I replaced the cartridge with an Ortofon 2M Bronze. This TT is a work of art. Wood plinth is perfect. Cover is as clear as the day it came out of its packaging back in 1975. I have the original hand written sales receipt $395 in 1975.
Should I consider swapping out the tonearm? I love the vintage nature of this TT. I would like to consider realistic options. And if keeping it just as-is should be the verdict then so be it. P.S. I've researched this TT and just cannot figure what TA was OEM. Does anyone know?
The TT is fed by all PS Audio components: Stellar Phono pre-amp, BHK Signature pre-amp, M700 (2 X 350w mono blocks), PowerPlant 12, all feeding DOM 1997 Thiel MCS1 speakers on Thiel factory metal stands. I live in a 150 yr. old factory building. Built like a bomb shelter. I have the TT sitting on a Solidsteel wall shelf lag bolted into 18" thick brick outside wall. Talk about isolation!