I speedrun SMB1, and my PB has reached the point where I want to move from emulator to console as to eliminate input lag. I have an NES, but not a CRT monitor, so I was wondering if any of you wonderful people could give me some pointers in regards to finding a good model. I would prefer 15-20 inches (60-75 cm) and up to or around $100.

If you're not looking for a top quality CRT (aka PVM, BVM, etc) then you can find people literally giving them away on Craigslist. I've seen people say that they'll pay YOU money to come take the CRT away from them. That's really the best way to find them. Either that or tag sales or pawn shops or any of them on the side of the street (just be wary of bugs).

As for a good model, there's really no "best" model unless you're looking for like RGB. You'll need the aforementioned PVM/BVM for the best quality or even something like a Trinitron (my personal model). But those can get expensive, as in a couple hundred dollars, so they're only for dedicated retro gamers mostly. Other than that, I've used various no name brand TVs before and all of them have worked great, plus if you're getting them dirt cheap, you can test them out and see if they work for you at little risk.