At least you know now! On my old Kiwi 17a the adjuster was so chewed up I had to get another one. It didn't hurt the drum any though.
So long as the drums are in good shape, smooth no gouges, not excessively worn, I'd just get the shoes and new springs. If the drums are good take some 100 grit sand paper and sand the inside surface, them spray them with brake cleaner.
The brakes are not self adjusting like cars. You have to manually adjust them.
2013 Jayco Jayfeather X20 E, 2008 GMC Sierra 1500 Crew Cab Z71 SLE