I would look for a good used mid 90's MB. Maybe a diesel
since you drive so much. It will be hard to sell you car for
$5k with the high miles , bad engine and paint.

Maybe you can get a engine+transmission from a junk yard
car with low miles?

Good luck! Dave

91 190e 2.6
73 bmw 2002 malaga
96 outback wgn