Rear View Mirror Replacement

Pardon the ignorance of a near future camper owner. But obviously the cab rear view mirror is useless with a truck camper. Is there a product that replaces the mirror or attaches to the mirror that uses cameras to work functionally similar to having a mirror? Are they commonly used?

I can only imagine that after forty year of driving, and as someone that is somewhat compulsive about watching what's happening behind me, that I will look up many times to see only a camper wall before getting used to using only side mirrors.