Just asking as your request is different then most. Are you sure yours are surge brakes and not 12 volt electric?
It may be possible, some of the real old campers may have had surge brakes. I just do not know what model years they switched to all electric. The ball coupler will tell real quick, that and the brake line coming out of the back of it heading to the wheels. (no wires at all)
If you do have surge brakes, do you know the name of the master cylinder on the trailer ball coupler? We can try and help you look for info.
The actual brakes themselves would look like/work an older auto drum brake, just odds are high they do not self adjust like the older autos did.
If you come up totally empty and no part names/numbers etc. then post some pics of the master cylinder and the brake shoes/ wheel cylinders. I have done some cargo trailers with surge brakes and I'm sure the ones you have are not that much different.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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