Any Ammo Collectors here?

I'm trying to find a value on a case of shotshells from the 50's.

What i have is Remington Express Extra Long Range. The number on the box is RX12-5 (5 shot) and these are the old red/green boxes... green paper shells and are mint!!

Anyone have a clue on the value? Or, anyone know of a good ammo collectors type forum that I can research this?

Thanks!!

I sell a lot of collectible ammo, these will go for 15-20 per box on gunbroker. If you the whole case you might do better but not a lot. I sold a similar full case a few years backs for around 275. Despite their age they are still pretty common

Thanks for the quick repy!

The only bad thing about GB is shipping ammo is a hassle. I have to drive all the way to the local (35 miles away) UPS to do it. Ouch!