I still see 51 cm TV's for sale at mail-order shops like
www.Wehkamp.nl and
www.Otto.nl but I don't like the price.
For that price, I would only buy new open frame monitors.
I've done the TV solution twice now and I'm not 100% satisfied with it. On my Galaxian, I've got some sync problem. It's "jittery" at the righ (=top) side of the screen. Strange, as this one worked fine on the Centipede before. The Centi now has it's original CRT back in place with a "new" working G07 chassis that I picked up for free in Germany !

What I really would want is to order a freaking pallet of 19" monitors. Nothing to beat a brand new CRT. However, even HAPP in the US doesn't carry them anymore (only 13"). I think the days are counting out for the CRT....
I think the TV solution is a great option, but I'd go only for more modern TV's now that have an electronic set-up menu so you can adjust everything (like the TV's Bruno used). Some older TV's simply don't have the controls to adjust everything needed.
There is also another way: You can get replacement chassis for a good working CRT for little money these days. Check out
http://www.grebo.eu/arcadegames/shop/index_eur.htmThey start at only 34 euro. Seller told me he said some people see geometry problems with that one. If you're anal, you should get the bit more expensive one of 55 euro (HQ).
So, if we could order a bulk order of real CRT monitors, would anyone be interested in a couple ?