cartridge for SME III

Hi, I always wanted a Sme III and I finally found one with the black titanium arm wand , I was told this is the latest in production. I have a Sure M97xe to use for now but want something better. I have a Signet transformer # MK12T so a mm or mc are both options, I also have a Monster Sigma Genesis 2000 Mk II cartridge that needs a stylus , I would spend up to $ 600.00 for a new cart or would I be better off to send the monster to Soundsmith? What do you use or suggest all opions appreciated . THANKS David.