mca,
That is a very nice table. It is called the AR Turntable built in the late 70's, early 80's if memory serves me right. It is a suspension turntable like the original AR-XA (like mine), but has a more refined arm with all the extra's like anti-skate and I believe this one had adjustable VTA. $550 is not a bad price as I have seen similiar go on ebay for about the same, maybe more. I think it would be a great starter table. Ask how the motor is if you are going to buy it and you may want to consider replacing the starter cap, as it is getting old. This is a belt drive table so you may need to invest in a new belt as well. Jelco arms were suppose to be very good. I think they made the AudioQuest PT series of arms, too.
Of course, if your interested in mine, let me know. Thanks for the reference WGH (Wayne)