I've used a feed throughs that came as CF bored out with a borosilicate stubs already attached, so that you can fabricate your own glass without having to know

I've used a feed throughs that came as CF bored out with a borosilicate stubs already attached, so that you can fabricate your own glass without having to know about the metal-glass bonding. I'm not sure how big those get if you're trying for viewport style usage.