Good gaming monitors are not expensive. Anything that supports G-sync should be fine. I picked one up off Craigslist for like $100. New isn't much more.

CRTs are not going to stay cheap for long. They're slowly dying to attrition. If nothing else, the phosphors are dimming over time. In fact, we might be getting towards the end of cheap garage sale pickups already. Especially ones that can be easily RGB converted.