I was working with optimizing memory on my pentium III lately for when i want to run more arcane dos games, and actually switched video cards because the BIOS on an nvidia card was so big that it was making it hard to map memory to that area… fun times.

Easiest: Find an old 4:3 flatscreen vga monitor that also supports composite. There’s a fair number of them out there. Best: retrotink but that’s going to probably cost more than the c64.