Trade for whatever. I have no use for it, and am not interested in converting it to hold plates.
If nothing else, it's a 4x5 dark slide for someone missing one!
Those make great wetplate holders with some slight modification, i.e., a little bit of foam weatherstripping near the door and a couple small pieces of whatever to position the plates. It's a lot easier than cutting the septum out of a film holder and stringing wire in the corners, or trying to use a dryplate holder for wetplate. Any aspiring wetplater should snatch this up.