This might be a good time to think about changing all the locks and keying them alike. I didn't have your problem but the major expense on my project was the entry door lock. I also bought a number of padlocks that I use for various things, all keyed alike. Now I carry just two keys for my 5er, I have quality locks all around, and I eliminated using the CH751 key found on all RVers keychain. I solved more then one problem for just a little more money over the entry door lock cost. I used RVLock. Hope that helps ...