With today's used car prices and if that's all that's wrong with it and it's still a good car that looks good, I'd get a second opinion on the cost and fix it right.
It cost me $1,000 several years ago to replace the main seal on my 2006 Ford Taurus. It was worth the fix because I still drive it and will run it into the ground. I kept it because it is in pristine condition, rides well and I like it. I have also learned how to do a lot of routine repairs myself.