Ask at the large and very active Yahoo Kenwood Hybrid group.
I first noticed that new restorer website recently. The parts store portion of the site is a Paypal website that closely remembles the commerce portion of K4EAA's hybrid site. http://www.k4eaa.com/parts.htm
The shipping rates are exactly the same. But there are slight differences between the offerings. One product in high demand is the remote VFO cable. K4EAA has been out of stock for several years. But TheHybridStore says they have them:http://www.hybridrestore.com/parts/
K4EAA has been ill for several years, and inactive. I bought TS-820 parts from his site last winter. His wife handles parts sales and they arrived in days.
What's needed is a reliable souce for matching paint. I don't trust the eBay sellers. A member of the Yahoo Hybrid group had several dozen cans of spray paint custom matched by an auto paint company. I bought some to paint the rusting top of my 820. It matched the bottom perfectly. But that stock is probably gone now. Needed too is a perfect hobby shop size touch up paint for minor front panel scratches. (anybody have a brand/color?)
Full restoration info is on the web. You can do almost anything yourself but watch out for the 900 Volts! N4NYY is correct that you don't want to invest much unless you're sentimentally attached to the radio. Like-new hybrids are easily obtainable in the $300 range, maybe $400 for a perfect 830.