A lot of quality, used CRTs go for cheap these days. Azatek seems to be one of the best. Ebay may be hit or miss... you don't want to be getting something that's very blurry/out of focus, or has other major issues.
Anyway my vote is for the Samsung 900NF. I was going to sell mine (although probably locally) for $90-100. I went to a 2005FPW and the image is no better on the LCD, except the text is alittle better on the LCD (I got it for other reasons like widescreen, weight/bulk, composite input, sexy) plus it is easier on the eyes. Still, I'd say the image quality overall was about equal, though obviously the blacks were fully black on the CRT.
A quality CRT that has been taken care of is a very hot buy if you don't mind the usual drawbacks. My Samsung 900NF was only about $400 new (back in the Onvia, Pointclick days) and I had it for almost 5 years, and it is just as good today as the day I got it. It was supposed to be able to go as high as 2048x1536, but I don't think I ever really got that resolution, I think it was never higher than 1880x1440, but even at that ridiculous resolution, the picture was amazing and I would've used it more if it was higher than 70 Hz.
edit: The specs were very good. Samsung sure made a nice one for much less $$ than the competing Mitsu or Sony. I think it was 1280x1024@100 Hz max, 1360x1024@85 Hz, 1600x1200@85 Hz. And while I'm at it, wtf is with 1280x1024?? I used that and 16x12 on the 900NF off and on for many years, then finally towards the end I discoevered 1360x1024. Now I knew why I read the few souls on AT saying to avoid that 5:4 crap. Whenever I see DoD:S at 1280x1024, it looks like a friggin' tunnel compared to 16:10, but even 4:3 is noticeably better than 5:4 IMO (in Windows desktop or in games, why oh why do they skip 1360x1024 in so many games??)