Pete, I think someone posted how they made a new cover for the Stash Box. Not sure if they made a new latch. Try a search to see you can find it.
I've still got the door - the latch has been broken off of it. Making a new one seems like more work than the results would be worth.
Last summer, while enjoying a few beers in the shack/shop, I decided a cleansing was needed. Loaded up half a trailer of wheels, frames, wiring and odds and ends. Posted it on Kijiji, the local version of Craigslist, for free. Got very little interest and nobody came around to have a look. So, off to the dump it went. Next day, as is usually the way things work, I needed one of the parts that had been binned. Pretty sure there were a couple of inner panels in there too. Broken tabs, cracked, but the stash doors were fine.