Okay.
Find me another Pinbot, in any condition, for sale, within 30 miles of 75240 zip code. As stated earlier, it's THIS market, Dallas. Things get snapped up here quickly, all the time. Very rarely do things posted on CL last more than a week or two unless they're horribly overpriced. I don't mind doing some work, and I didn't say for sure that I would pay 600$ for this machine..I'm going to negotiate and I expect to pay less for it than 600$ given that it doesn't even power on.
I've been trolling CL for D/FW, Waco, Oklahoma City, and East Texas for months since I got my Space Shuttle. This is the first pin that's come up that I would personally consider a "grail" for me. It's one of the games that defined how I look at pinball, albeit via the NES, but I have played it in person before.
Shuttle wasn't a grail, but specifically soundwise it's that 80's arcade sound I remember, and I've been interested in NASA pretty much my entire life. I'm spending a lot of money on restoring Shuttle, but all said and done, and I mean EVERYTHING (LEDs, Ramps, shuttle toy, drop targets, playfield, plastics, stencil kit, pinscore power supply and LED segment displays..), I expect that machine to cost me ~1900-2000$. Yes, it's a lot. Yes, I could probably find one in really good condition before spending all that money. It wouldn't be mine, and I wouldn't care about it in the same way.
Personally, I don't mind the work, as long as it's not an impossible situation...I can't deal with acid damage, or rebuilding traces on a PCB.
Final point: "Similar" is just that. Can I pick up that era of pin working for cheaper or same price..maybe...but is it Pinbot...no. =\