I wouldn’t restore it at all.
This is what a lot of guys who collect stuff like this do.
Use regular old WD-40 on the exposed metal. Just use an old towel, not anything especially abrasive. You can put it on and let it soak for a while, then rub vigorously. You should get all the crud but none of the metal or parkerizing off this way. When your done with that put a little light oil on the blade (I like Remington aerosol gun oil, but any light oil will do). Unless the leather is really dry I’d leave it, if it is I’d use a little oil on it (and / or the sheath) too.
This is more a good cleaning than a restoration, which I agree is probably not something you need or want to do.
If you do want to go that route you’d need to strip the handle leather off, remove the finish, do a good sharpening, re-parkerize and then put a new leather wrap on it. You probably want to find a knife-smith to do that for you, if you need to go that route. (Say if the above doesn’t result in satisfactory results, or the blade is deeply pitted or rusted).