Can I use a silicone keyboard cover rather than replace missing keys?

I have a 13 Inch MacBook Air - Model A1369 with 26 keys that need replacing. At minimum it will cost me $130 to replace them all individually, that is a bit out of my budget right now so I am wondering if I can buy a silicone keyboard cover and use that in the interim.

The suction caps are still on the keys and they work perfectly, so I figure the cover would not only stop excess grime from getting in but also enable me to use the keyboard functionally until I can replace the keys.

But I am no pro nor a regular MacBook user, so any advice is greatly appreciated 🙂