In my limited experience, and the fact that I live in Canada, I have found these tubes insanely expensive when they do pop up, and they rarely pop up. I may just suck at eBay searching.Even though this is an old thread now, it's worth adding for others reading it that it isn't difficult to get replacement CRTs for compact Macs. They appear reasonably often on eBay, along with parts machines. In a case like this one, that is what I would do rather than strip an otherwise viable vintage system and dispose of the rest
There are even some who replace the CRT with an LCD panel.
Also worth noting that it is easy to discharge any residual voltage from the CRT anode when working inside the system, and that the Classics have a 'bleed' capacitor which discharges the CRT when not powered, so with care there's little danger.
I suspect that like everything to do with old computers, it's about the luck of the draw. There are a few on eBay (US) right now and they typically go for $35-$45 (again, US). These CRTs are interchangeable between some of the compact Mac models, so not just Classics.In my limited experience, and the fact that I live in Canada, I have found these tubes insanely expensive when they do pop up, and they rarely pop up. I may just suck at eBay searching.