Rear main oil seal in a 95 accord ex

[Benji999]

I have a moderate oil leak in my rear main seal and it was recommended to me that I replace it. My car has 345,000 miles on it, and I was told the engine has to be dropped to replace the seal. How much would a mechanic normally charge to replace it? Also, would it be in my best interest to just put a new motor in it since the old one has to be dropped out anyway??