It doesn't really help much with your camper being stored so far away. Our Dexter axles had a label or were stamped with part number information. You may be able to get the information you need without pulling the rotors... but will have to crawl under and likely have to do some research online.
I did have a bit of a challenge getting the right seal for our Dexters... the part number on them was the Dexter part. The first auto parts store I visited could not find the correct cross reference to their stock items. The second parts store dug a little deeper online and found the right seals. Bearings may be the same.
Happy Camping!
John.