First off, join the
Uhaul Facebook group. It is speculated, but not known for sure, that all the campers were keyed alike. I know my key fit another owners
Uhaul. There would have been a limited number of key variations so maybe we were just lucky. The latch is a Bargman L300, long out of production, and frequently
for sale on eBay at inflated prices. Originally they
sold for about $100. Sometimes the lock cylinders come up on eBay. Note that there is a small pin on the side of the lock cylinder that has to come out to remove the cylinder. If you can find an older locksmith they may have a master key or can make you a key. My locksmith had to order the Bargman key blanks for me. Another bit of info; to lock the door using the inside lock rod, the lock cylinder has to be centered in it's rotational travel, that is turn key one direction, then other direction, then halfway back so it is centered.