Ammunition like that has a very small group of people that even know what it is. Many would give you a buck a round so that they could shoot it.
That isn't the thing to do with that stuff.
First thing to do is wrap each package, separately in Saran Wrap or its equivalent.
Then start searching the web. Try something like "metalic cartridge collectors assc." That may get you some place to start.
In Kamloops, this spring, there were two packages of that stuff with stickers of $75 per package and single rounds at $5 each. Both packages sold on the first day, in the first hour. There were several single cartridges still left around 3PM.
Some guys want that stuff as accessories to go with a period rifle. Some just want to round out a collection. Some just want to hear it go bang. Your choice, dig a little and maybe make a deal with a collector of cartridges on a different site. There don't seem to be many here that are really serious.