Originally, I tried key tags, can coolers, jar openers, etc. and the only thing that works for me is coffee mugs. I ended up selling my flat press. I think too many organizations give away the small stuff at fairs etc. and people don't see the need to pay good money for them. I now do just coffee mugs. The majority of my business is wholesale via the web. I have sold direct to a few state parks but that is a tough way to go. Either their budget is already gone for the year or the state has cut their budget so much that they can't try anything new. I just printed 6 dozen for a cultural center and have another 6 dozen for an area photographer that will be selling them at an art show. I also have orders for a dozen each from a couple state parks. however, January - May were extremely slow for me.
Being a wildlife photographer does help as it's my photos that are printed on the state park mugs. It's actually the reason I got into dye sub. I needed a way to sell my images besides just prints.
Good luck.