If you've got some terminal pin crimpers and some patience, it's not too hard to make your own. I've made several myself. The most frustrating thing about making your own is that there is no standard for VGA wiring. From one to another, they use different colors, and sizes of wire and handle grounding and shielding differently. The most time consuming part of the process is identifying which wire is which. If you're not able to make your own, Ultimarc sells them for $12.
These were made for Wells Gardner monitors, but also work with Vision Pros.
