Are you talking about skirts that close up the fender opening around the wheel?
Just my opinion, but things like that only belong on CARS!

If you REALLY want them, there are places that can fabricate them. I'm trying to remember one that Jim Carter uses as a supplier of some of their patch panels, but the name escapes me at the moment. I'll probably remember it at about 3 AM.
Found the shop I was thinking about. It wasn't a 3AM thing, but a search thru posts till I found a reference. Here's a
LINK to Wheelwright Restorations.