In terms of design, quality, and best bang for the buck you really can’t go wrong with the Tesla wall charger. I have the same situation where we have a Tesla model three and a Rivian R1 T. I was able to pick up a Tesla wall charger for 350 bucks and it outputs 11.5 kW. I purchased an adapter on Amazon that converts Tesla to J1773 and it works perfectly for both the Tesla and the Rivian, The Rivian is able to make full use of the Tesla charger power and sucks down the full 11.5 kW. It is I believe the simplest and cheapest solution and is an incredible value.