There are many. The Grado Sonata, assuming proper matching to the arm, is a player in the $500 range. I have owned one for over five years and used it on a VPI 10.5 and Rega RB-300 to great effect.
Best $500 cartridge? Dynavector DV-20XH?
I'm looking to upgrade from my Grado Gold cartridge, its about a year old, and i've heard good things about the Dynavector DV-20X 2.5mv output. I have a killer channel islands VPP-1 phono preamp with VAC-1 power supply and custom DH Labs IEC cable. the cartridge is going on a Project carbon arm on a modded Project XPression table that's also a year old. Any suggestions other than Dynavector? What would I gain from upgrading to the $500 range?