I believe Napa can help you find bearings and maybe brake shoes for these brakes. But if you need any further parts, it's hit or miss. Some Dexter stuff may work, may not. Eventually it makes more sense to replace the whole axle because they are cheaper than you think.
I believe the backing plates are not compatible though, bolt pattern is different.
2007 T-286SR Cherry/Granola, #6236, original owner, current mileage: 9467.8 (as of 5/26/19)
1997 T-2653 Blue Denim, #5471
1979 12 1/2' MC, Beige & Avocado, #4639
Past Sunlines: '97 T-2653 #5089, '94 T-2251, '86 T-1550, '94 T-2363, '98 T-270SR