Until you find a new set, you can clean them up good to get the oil off as much as possible, and build up a nice layer of JB-weld epoxy (you can use some masking tape to help mold it. Let it cure, file/sand it a little as needed and then have a useable set until the new ones come in. I know of a couple of guys who did that after similar situations happened to them.

If you have a propane torch, you can get some aluminum solder and fill in and build up the rocker covers using that stuff, and file/sand/dremel it to shape it some.
I actually did that with a OS Surpass engine years ago when i did the exact same thing you did with a P51 Mustang on a belly landing.