@TorbYorn Well, tightness of course depends on your size and preference but this website has great tools for finding exactly what you want. If you go to Masturbators > Sleeves & Onaholes, then you can use the filters on the left side to restrict by size of toy (small, medium, large), tunnel length (in terms of inches for your personal size), as well as softness (1-10, where 1 is the hardest/firmest). So if you use their search filters you should be able to find something pretty easily. Personally, the Furu-chu series is fun (dual-layers) tend to be tighter in my opinion and as well as Gokusai Uterus and Lolinco.

Lastly, you can also just search up "hard" or "tight" if you want quick and dirty results.

@TorbYorn I've found this Furu-chu Sour Immature Lemon is super tight for me. Honestly so tight its difficult to use. If I can devise a way to use this hands free I think it would be a lot better

@TorbYorn ToysHeart is a brand that makes a lot of super tight onaholes. When looking at their little rating system graphic, you are looking for a star in the far right upper area of the graphic (far right red/orange area).