Clear coating for protection

Ausf,
You might try your hand at a clear epoxy enamel that comes in a spray can, or even one of the two-part epoxy paints, except you would have to brush it on. Either way, when dry the material should be as hard as a rock. Granted, any paint can be abused, but the epoxy should last somewhat longer, and you should also be able to wash it (if you wanted) without it coming off. In addition, you may want to consider an epoxy primer before the epoxy topcoat/clearcoat.

Hope this helps some.
Gip Winecoff