Ideas for a keyboard cover?

I need a keyboard cover for a Dell keyboard, Model RT7D50

Of course, it is a slightly off-kilter shape from the standard keyboard. Dell’s quote for a cover was $26. To me, that seems like an awful lot for a piece of plastic to cover a keyboard.

Anyone ever do a homemade/custom made keyboard cover themselves?

Any ideas are appreciated. Thanks!
Tink 🙂