Never done this, but , perhaps a different seat track could be available, a driver seat, with higher adjustment, installed on passenger side ,etc.,etc. Don't wish the op to get rid of a good car and get a bad car. .02Great idea but what would that be with an elderly dad? He likely needs help getting in and getting out and it may be causing discomfort. The car is just too low. I recently helped daughter drive her new Jetta from Az to Tn and after 3 days had had more than enough of getting into and out of a sedan and I'm 68 and in great shape.
The OP might be able to put riser blocks under the passenger seat mounting feet and raise it up an inch or 2 to help temporarily and/or add a firm piece of foam on the seat bottom. Not ideal.
Agree with looking for non-mainstream CUVs to keep the cost down.