not sure if we have the same axles but are campers are the same year and mine is a little bigger. I replaced a set of brake shoes and adjusted all 4 wheels this past spring. Most will try to sell you a "complete" assembly (backing plate, shoes, springs, actuators and drums) anymore. I only wanted new linings since everything else seemed to look fine. I had to do a little searching, but my local NAPA auto parts store was able to find the shoes I needed. If your handy or have had experience with replacing drum brakes, id say just replace the shoes, if not, do the whole assembly. I think you can call Dexter and they can give you the part number that will work with NAPA parts. I still have the box at home, so if I remember, I will get the part number off of it. Chances are they are the same... I think the 13.3 is the drum size? 13 inchs in diameter and maybe 3 inch wide shoes???
'97 Jayco Eagle 314BHS
'03 Tahoe LT 5.3L