cart upgrade question.

I will list the system so you dont have the click.

TT: VPI Scout with JMW-9 and Dynavector 20X-H
preamp: David Berning TF-10
Amps: Berning EA-230's in mono
speakers: ESL-63's or Tannoy Gold 12's
Cables: Grover UR's

My question is what upgrade will give me an obvious upgrade in SQ without spending more than 800-900-1000 bucks? I dont mind buying used a low hrs cart.
Just wondering also if the system is up to task for a better cart.
Presuming your 20x has some milage I would maybe look to an outboard phono stage. 1st the 20x is a pretty good cartridge. 2nd, presuming you are using an inboard phon, if so I am not familiar with it but, two outboards I have listened to that I think would give you a noticeable upgrade.

1 Dynavector p75 or the new PS Audio unit. the PS edges out the p75 on pur dynamics and bass extension but the p-75 way out performs its price range in tonal accuracy, timing and transparency. Factor in cables and you in your range.