Can I install a new arm on this old table?

The KD-500 came with two circular cut outs for installing a tonearm. One was drilled with a concentric hole, the other was an SME slot. (You'll probably want to use the circular hole.) It should be a simple matter to attach a new arm, provided you have the instructions and fittings that presumably came in a package with the new arm.
It shouldn't be any more difficult than attaching and fitting a cartridge, and no soldering should be necessary.

Thanks for the reply! How do I know which arms will work and which ones won't? Recommendations?

A Rega should work and would be a good choice. You'll have to use spacers to adjust the height. With this tagle I wouldn't spend too much on an arm - maybe you could look here for a used one.

Brusson: thanks for your help, much appreciated. I found an RB300 for less than $200, which is on its way. Do you know where one can find these spacers you speak of, and how they're used?

Also, I'll be looking for a cheap MM cartridge. Suggestions?

Thanks!

Rather than; spacers I would suggest a nice VTA adjuster. The best one does not require the arm to be removed to change the height (as in with spacers; major PITA).

Thanks for the suggestion. Can you recommend a decent but cheap VTA adjuster along the lines you've specified?

...the one from Pete Riggle Audio was well reviewed in "Stereophile" a while back and I think Express Machining might make one too.

The Pete Riggle is far more money than what I want to spend. I might just have to go with the spacers. Does anyone know where to find them?

Thanks!

Reeds,

Goto www.britaudio.com and get a Incognito Easy VTA Riser. They run about $50 shipped and will allow you to adjust VTA. I got one for my Moth Alamo (P2) and still use it (although I did 'cut' it a bit smaller) on my VPI. Cheaper than spending over $100 for a Super Armboard.

Marty