Oracle Turntable Service

I would look for used Mkiv or V as well before upgrading. The newer versions have improvements 'o' plenty:
Suspension towers and adjustment
Bearing
Powersupply
Counterweight
Arm Board
Rubber Mat

I bought a MkII from a friend that had a few upgrades that sounds good, but If I ever run across a IV or V I'd scoop it up and sell the II.

Happy Listening

Oracle sells a tune-up kit for $150, includes new springs, belt, etc.. take a look on their website for complete info.

In terms of upgrading I think it'll cost way too much to bring your MK I up to snuff. Probably be better to buy a used MKIV or Mark V. As an example I found a used Mark IV with turbo supply, SME 5 arm, and Dynavector pick up for $2500 for my boss.