If native 15khz is not a priority, then I would just go the LCD route. I contemplated jumping on some of the last remaining CRTs, but later realized the depth is just too much for my needs. If you go LCD you can make the cab with a very short depth, say 12-20" monitor depth. It wouldn't have the same aspects as a real arcade, but a lot of people are building these to go in homes. Once you build a deeper cab with arcade machine aspects, you need to account for a deep control panel (This is where the depth REALLY matters for comfort), then the space for people to sit or stand at the machine. If you go with regular arcade depths, you're easily looking at ~6 feet from the wall for all this space. I just don't have this amount of room!
So in the LCD arena you have 19-21" PC monitors, which I would recommend: 20" HP LP2065 or 20" Dell 2007FP. Just actually picked up an HP model refurbed on ebay for $140 shipped. Not the best deal, but a decent price for a good monitor. A lot of folks have given the +1 for these two monitors. There are a lot on ebay depending upon whether you want new, used, returnability, etc.
The other route is LCD TV, which I think virtually ALL of them are widescreen. I personally don't care for this route due to the black bar issues, no matter how you mount it.
I plan on making a rotating LCD with the LP2065, completely covered mask. But alas, that is sometime down the road yet. Still doing a lot of research!