Matt,
Speaking from a rough idea as to what runs and what doesn't run at MNG, you'd be more likely to see any combination of Monson 0-4-4T's #3/#4, and (or) #7. #8 needs FAR too much work (everything that is currently being done to #7 PLUS a problem with getting steam to the engineer's side cylinder) to be a plausible rebuild in any sort of near future scenario.
Like it has been said in other places on this forum, it all matters on how much money you have. All of the Maine two foot museums would love it if one of their members hit the $100 million Powerball jackpot and donated a chunk of that, but the fact is that the museums have to work with what they take in from tourists, grants, etc. The WW&F is a shining example of both volunteer loyalty (as seen in their annual income just from member donations) and shrewd business decisions. If funds aren't available and it isn't an immediate need (a thread I had read about 60# rail a while back is a good example), then it can wait.
I too would like to see 3, 4, or even all of the surviving Maine 2 footers together under steam sometime (wouldn't THAT make for a good smoke show), but don't hold your breath, it might be a while before it could happen.
Bill Piche
Fireman
MNGRR