I found some nice brushes on the web and made this into a collection. I'm not sure if it fits LuxRender material database, but you can vote for it. I can make more/different ones, others are of course free to create their own.
Currently there is this (old one from me):
I can also change this one if you want.
You are free to vote.
Reason for font: material database is many different materials => many different fonts used