Actually now that you mention it I think you are half right after looking into it more.

It does seem like it is actually heavily regulated and not necessary illegal, but I guess this would mean illegal for unlicensed people to sell.

If I had to guess most sellers in the us with tritium in their products aren’t selling tritium but rather selling procured items with tritium and thats probably a legal workaround for that.

Ohh I think I got confused when you mentioned plug, I guess you meant linking to your post

Ooh do you work for glow rhino?

Name checks out