Rebuild or new cartridge with my zeta tonearm

I think I would like to stay under $500. That is about what it will cost to get the Sumiko overhauled..

Birdfan, 16 gms seems a little heavy for that arm but I would certainly stay away from cartridges with a compliance over 20 u/mN. If it is indeed 16 gm then you had better stick with the Clearaudio cartridges which are down around 15 u/mN. Most MM cartridges are over 20 u/m. Soundsmith has low compliance cartridges but they are all low output. I assume since you were using a high output moving coil cartridge that you do not have a high gain phono section.

I actually bought schiit’s entry level oh I.. which has all kinds of settings for a range of carts. I believe it will do LOMC. I guess I’ve never been sold on MC as they all seem so expensive.. but I do have preamp

If you were happy with the sound of your Sumiko go for the rebuild it should sound as good if not better than new.
I had my Sumiko BPS Evo 3 rebuilt and was very happy with the results

I very much doubt it will sound better than new.
It will definitely sound different.
It will definitely not sound the same.
It could sound good.
It could sound very good.