Not trying to rain on your parade but 7-bills might be a tad high for even a fully working Flash. The displays and decent backglass do help but you might be better off just fixing it. I suggest you re-flow the header pins on your boards (sounds like cold solder joints causing display issues) and replace that 40-pin interconnect - my guess is that will take care of most of the problems. Get it working and then sell it if it still bothers you.

I've seen this scenario play out countless times:

guy overpays for machine.
machine develops issue (on its own or from being incorrectly 'fixed')
can't\won't learn to properly fix or have fixed
after fishing no more than 3 days for someone to overpay for project, parts it out due to frustration.

Even after being offered help and services to assist to get this pin repaired, guy still would rather part it. wow....

I would have been interested in the whole thing because the issues are very minor and easy to fix - however I would only be in at a price that would make sense for a non-working flash project. Like I stated earlier, 7-bills was more than fully working flash pins fetch around here...

I'm going to be keeping my eye on the OP - he's got a few machines in his collection that will develop issues at some point and we'll probably see this play out again.