Thanks for the background. Really appreciate it!You need a base or bases specific to the rifle. And from there, you need rings of the appropriate diameter and height and finish, that are selected with your chosen scope's tube diameter, positioning and objective bell clearance in mind.
Like most things in life, scope mounting isn't rocket science. But there are indeed things to consider, all of which become easier once you know how. You can always have a shop mount and bore sight a scope for you. I'm not sure that my first attempt would involve an expensive scope on a vintage rifle.
Freedom is similar yes. I actually have an older model 3x9x40 VX-2 on my 336. The Freedom series is Leupold's replacement for the older VX1 and my VX2 series both. They transitioned from the VX1 and VX2 to the new Freedom line some 5 or 6 years ago now.
The VX-3 series is the better scope over the Freedom. Also, the vintage look in 1973 was a gloss scope, on what is your gloss blued rifle. So, the combo is an aesthetics thing. A "period correct" look may or may not matter to you.
If you do care about that? And if you look for and find a used scope in gloss, rather than today's matte finish? Leupold has a lifetime warranty. And you don't need a receipt, nor do you need to be the original owner. So no worries there.
As mentioned, any new scope will be matte black, rather than gloss black. A gloss finish in new production product of any series is (sadly) no longer available. Same with the finish on most rifles today. Matte black with that also, in most cases with most new rifles made today.
So you have some things to consider. Take your time and have fun with it!