Yea, I'd personally be more interested in something more of a cabinet, screen glass, and marquee with no control panel top.
Basically, something that would allow me to use my own paint/graphics, CP layout/overlay, and hardware (joysticks, buttons, monitor, etc).
Because of the high overhead of the plywood/MDF sheets involved, I wouldn't see people paying more than $150 over the cost of the build materials. Shipping would end up being in the $100 range for ground so that leaves $50 profit which has to cover remaining expenses.
You might find some people interested, but $150 over cost would be close to the "just do it myself" range.