Cheap generic keyboard / TKL covers for MX?

I’ve got an Orange TKL keyboard cover finally, and it’s great. Another brand on the way as well.

For the more generic factory keyboards that didn’t ship with a cover, is there something commonly available from Amazon or big box stores? I’ve got a household Varmilo here that didn’t ship with a plastic cover.

I know Amazon has all those silicone protectors and stuff, but I’m just looking for a cheap plastic cover you put on the keyboard when you’re not using it - better if it’s known to fit Varmilo or similar major MX prebuilts.

This fits full sized; so maybe a TKL + mouse underneath?

full sized cover

I feel like someone could clean up in this hobby selling vacuum formed covers for various boards.