Sarting problems w/ 300TD

I fear for my starter. Or I guess my wallet. 5 months ago I bought a 1985 300TD with 360,000miles. Shortly after that, on a long, highway trip, I stopped at a McDonnalds, and the car didn't want to restart. No sound or turnover, just dead. After calling the 800 line, and "jiggling the wire harness", and turning the key quckly on and off 75 times or so, it started. The problem has never repeated itself. But now there is something new. Tried to start it the other day and got an unpleasent ckkkeeckk sound. and no start. worried some, tried again, same sound. worried more, played with shifter, in and out of park, then tried again and it started. This has happend about 3 more times. Sometimes it starts without a fuss, but I'm avoiding driving it. I don't have a mechanic I trust here yet, so I really need some advice. Such as, what are the possibilities, what should I check ( or rather a mechanic, since I don't know squat) and if it is the starter, what is a fair price for the part and labor. And where can I get a rebuilt one. This new and clueless Benz owner greatly appreciates your help, as well as any shop recommendations for upstate NY. Way upstate.

------------------

Jeff
300TD 365,000m