They are a sweet non-bell pepper and several types of sweet non-bells are available from various seed companies that carry a large variety of tomato and pepper seeds, like Tomato Growers Supply Company and Totally Tomatoes.

The mini-bells I've grown are truly miniature and smaller than the sweet non-bells, running about 1-1 3/4" but the smallest of the sweet non-bells I've grown run 2-2 1/2", so I think maybe those are the ones you want.

I believe the variety that might be what you're looking for is "Yummy", and I've seen it sold as a mixed seed packet with peppers in several colors and also sold only as "Yummy Orange". I'll find and link Yummy Mix below.

Here is a link that might be useful: Yummy Mix

That looks like them. They are very expensive in the stores and I have never bought any, but they have been showing up a lot lately at coffee hour. Very good flavor. I'm adding them to my salad garden and planting them instead of banana peppers next year.