I did re-build the entire player mechanism for a baby grand player piano one summer when I was in high school.

I do some wood working now. I would suggest if you want it to be portable you could use 1/4-inch plywood. That would be flexible enough to bend etc. Light weight. You could also go for a modern look and go with a corrugated plastic or something of that nature with multiple colors to choose.

Having it easy to break down and transport makes it harder to choose the types of materials for you. Perhaps Styrofoam covered with a black lacquered veneer would appear to be made of wood but very light.

Have fun. Sounds like a fun project.

- Brian