I have several kits that I plan on incorporating into my Franklin & Bath RR layout when the day comes. Since I'm sure there are plenty of other modelers that build the other Maine 2 Footers in HOn30 that look at this website, I want to share what I know.
WW&F Enclosed Water Tank kit
This is an out of production Sandy River Car Shops kit. As usual, have patience and diligently search on Ebay for it.
Backwoods Junction Station
This is a Laser-Art kit and it IS in production. Technically it's not prototype, but it's basically a selectively compressed model of the Station on the WW&F that was located at the intersection with the wide-gauge Maine Central Railroad at Wiscasset. If you're modeling the WW&F and use this kit, and somebody says something about it, ask them to see their layout of the WW&F to see how they did theirs. Nuff said.
Monson Station
This is a Hodgdon Company Craftsman kit. There are a lot of things to like about the kit. The instructions include maps and photos of the prototype, and there are even actual photographs included with photos of the prototype and interior construction details of the kit to help you visualize it. There's a color-coding sheet included so that you can just look at the sheet to see what color the size of the lumber you're looking for is painted on the tips, so you don't have to repeatedly measure lumber to make sure you're grabbing the right pieces. Grandt Line windows and white metal door and whatnot details are included. And LOTS of white metal box and barrel and crate castings. So many that you can clutter up the station platform really well, or use some on this kit and some at other structures on your layout.
Kennebec Central RR Randolph Depot
I don't remember who makes this kit, but I do know it's still available, and when I figure out who makes it again, I'll post that here. I bought this already constructed from a friend. If you don't like Randolph Depot, there's seriously something wrong with you. It's like not liking Marbles Depot on the SR&RL. A nice touch are the doorknobs, and looking at this means that I will have to go back and add doorknobs to every structure on my layout or I will someday be turning over in my grave haunting over it.
Kennebec Central RR Randolph Enginehouse
I also bought this kit already assembled from the same friend I bought the Randolph Depot from. Photos coming soon......