Wife of hubby whom Inherited Fathers 450 Marlin

Welcome to MO from South Carolina.

I agree with 10acres above comment in which he recommends a 2-7 scope for the rifle. I have number of such power scopes on rifles and I usually leave them set on 3 or 4 power and on the rare occasion I need a higher power, I can increase the power with a twist. In my opinion, you just don't need a high power scope on a rifle that will probably be fired at close to intermediate ranges.

Don't go cheap on scopes, however. There is a marked, noticeable difference between the econo, cheap scopes and Leupold or Vortex. I prefer Leupold scopes because of quality and warranty service but Vortex is of good quality also and their warranty service is probably as good as Leupold's. My purchase of Vortex products has been driven by financial considerations at the time of purchase, otherwise, I would have only Leupold products.

.450 Marlin has stout recoil so I don't think a cheap scope would survive for an extended period.

Consider Talley mounts to mount the scope to the rifle.

In the near term, consider going to some of the bigger on-line ammo vendors and request to be notified if .450 Marlin becomes available.

Good Luck

Hayman's idea has merit. The ballistic difference between the 450 Marlin and the 45-70 is nil. I'll come back to that in a moment.

Unless your pockets are very, very deep, you will not be able to afford factory ammo for your 450 Marlin. Even then, you would need to buy up as much of if as you could find--as much as you ever expect to shoot. And you would need to buy it up as soon as you find it. There just isn't any of it being regularly made at this point in time. Even if one or another company were to produce a run of 450 Marlin--and no one knows when or if--it would still be in short supply and expensive.

You could make a hobby out of it. Start going to gun show, flea markets, estate sales, etc, looking for 450 Marlin ammo. Buy what you can find. Buy factory ammo, brass, and re-loaded ammo. Pull the reloaded ammo and save the brass and the bullets. It could become an interesting quest. Send your shooting friends out looking for 450 Marlin when they go to shows and estate sales. You will feel great when you score a box or two. You will travel, and learn about guns. You will also need to learn to reload. Fortunately, straight wall calibers are easy to reload. You will cry a little every time a case develops a neck split. You will learn to anneal brass. This also will become fun and very satisfying.

About that re-barrel to 45-70.... That's actually a pretty good idea if you really want to shoot and hunt with your grandfather's rifle. Factory ammo will cost you.... what? $5/round. For the price of 5 boxes of shells you could have it re-barreled to 45-70. It would solve your ammo/component problems and you could shoot it as much as you like without worrying about when you'll find another box of shells.

Think about it.

Come back here with your questions. Either way, we'll help you make it happen.