As other have said, I'd leave it alone. Keep it clean and lightly oiled. If this is something to be passed down in the family, the honest wear is part of what makes it special.
If you do decide to reblue, because this rifle has sentimental value, please get it done properly. There's nothing tackier than nasty, stinky cold bluing.
Cold blueing is meant for tiny scratch repairs, etc. Smearing it all over your rifle will completely destroy it's value, and after with that horrible smell on your hands for a week every time you use it, it will degrade the pleasure of using it too.
Just my opinion.