Is it pretty easy to have an auto glass place remove my windshield and redo the seal?

Chances are they won't want to save both the glass and rubber seal while removing.
I would look over the rubber seal first and if nice save it and replace the glass.
Old glass has many pits from sand and has lost its sheen. I dont like to reuse windshields as wipers don't work as well on old sand pitted glass. It can be done but not worth the extra effort in my opinion.
I have done it to save a buck on rare windshields (50s cars) but always regret not going with the new glass. Your eyes will like the better visibility rain or shine.