I have a 410 shotgun made by the Cycle Works of Iver Johnson. It is a single shot and I would not trade it for anything. It was my first shotgun, given to me about the end of WW II. I skulked around the stream bed of our ranch laying waste to rogue elephant, man eating tigers, and living off the land as an imaginative 7 year old is wont to do. Actually, most of the critters were probably quail and cotton tail rabbit.
Don't have a clue what yours' is worth, mine is priceless.

I posted a picture of my Iver and Johnson o/u on the snapshot section of the main page.you can see the i/j emblem on the pistol grip.

I have an I.J. 16 ga single shot that my granpa owned. It's the first shotgun I hunted with and like Happy Miles mine is priceless.