any cinematronic game is uncommon. Working is rare. Don't know what it is about them, but they are always missing side art. Cabinet material sucks as corners break really easy..
You have monitor problems, board problems, and power supply problems. So not easy to fix. I think you should have a good idea how hard they are to repair from your sundance effort...
I would think most cinematronics games ended up in land fill. I have had maybe 8 star castles over the last 20+ years. Since its one of my favorites I pretty much grabbed all I could find.. I have maybe 8 SC pcbs on my board rack. I think I have only crushed 1. So someone else killed a few..
If you really want an AA, I have 2 cabs.. I also have a kit for SC that will let you play ripoff and SC on a rotary switch..