Shit, I have an entire XM200IN that I want to give away (unkown if it's the tube or chassis that's bad). What happened was the chassis was recapped and it turned on and was working. Then went to adjust the B+ and as soon as the B+ pot was turned the screen went dark and murky - could it just be a simple pot replacement? Or maybe the old tube just died? Never went further with it or cared since I was never planning on using this monitor because of the burn in, I just wanted to see if it could be fixed with a cap kit which is where my repair skill end with monitors. If you where closer, you could have the entire thing for free and try it.
Can't you send your current one out to someone to repair it or are you totally missing a chassis?