If you have a build sheet for the 5er it should list the converter. Odds are you have a WFCO . You may also be able to get model from the unit ( should be in the same area as the fuse/breaker panel.). Just to be sure check current model as some new WFCO are supposed to have 4 stage capability. The progressive site will provide direct replacements for the one you have. As you have 4 sixes, you might consider a slightly higher current model ( as long as it has the same dimensions.) Switch out is fairly simple if you can do basic electrical connections.
Avatar needed a change will go back later. Barn owl is one of our raptors as well.
Progressive site RV & Motorhome Power Supplies, Converters and Centers