Phono Amp recomendation

I am currently using an old Adcom GTP500 receiver as my preamp and phonostage for a MMF 2.2 turntable. It sounds "fine" to me, but I've heard that much improvement would be gained from a dedicated phono preamp. Need to stay in the $200-300 range unfortunately.

Side question, anyone had any luck with the herbie record mat?