Shotgun "Slug" Sights.
I have a Mossberg shotgun that came with 2 barrels. One is 28 inches long and the other is 18.5. One is for hunting and the other for home defense. And, I think that they will serve well for those purposes.
But, I have a quantity of shotgun slugs. And, the sights on both barrels is not that good for shooting slugs. I would like to install rifle sights on the short barrel. I did a google search for "slug sights" and I found that they are available. Some mount in a dovetail (I don't think so) and some mount with screws (probably the better option). And, I don't think the prices are really outrageous. But, I would probably want to have them installed by a gunsmith.
However, I was recently looking through some back issues of gun magazines. In the January, 19991 issue of the NRA's American Hunter, on page 79, there is an advertisement from a company named "Innovision Enterprises." They had 2 different types of slug sights. One set mounted to the ventilated rib and one set had a band that went around the barrel. It looked to me like anybody could install them and remove them as needed. I would really like to get the set that goes around the barrel as my gun does not have the rib. These sights are called "quick change" easy on and off. They were made from nylon. They were fully adjustable. They were said to be non-marring.
I did a google search for the company and found that it is no longer in existence. I also searched for these types of sights to see if someone else offered them, but no such luck. Maybe they were not dependable. People may have tried them and found them to be no good. The company may have been unable to sell enough to continue in business. I don't know.
But, I hope that I can find something that will work for my purposes. I am an ex auto mechanic, so I can work with my hands. I suppose that I could drill and tap a barrel to install screw mounted sights. And, that may be my only option. I'll let you know.