If you have trouble finding the hangers I have been using the "taco" method with my 2.25x3.25 film and it works quite well. I am able to dev. 5 sheets at a time using a regular reel tank.
Arthur
Boy, I wish you'd placed this add last week! I was at an estate auction this past Saturday where the guy was a big fan of the little mini-Graflex cameras. There were holders and a stack of these developing hangers. I bought a couple of larger sized contact printing frames (3 1/2 x 5 and a larger one,) but as I recall no one wanted the developing hangers. As far as I know, they were still laying on the table when I left the auction. They probably threw them out. Sorry, I know that wasn't what you wanted to hear!
I've seen them show up on that auction site fairly often. I bought about a dozen 3-1/4x4-1/4 developing hangers in the last 6 months. I think that there were a few 2-1/4x3-1/4 hangers mixed in. A little patience goes a long way.