Not sure why you think slider calipers are hard to come by, they were in production much longer than the pin types, all the way till the end of M body production in 89. Reman ones are readily available and Doc DIff sell news ones for a similar price.
For some reason all the parts stores don't have them (even rockauto). Dr. Diff was out of stock until yesterday.
Rockauto can get the calipers in stock, but not the brackets. That's not part of a replacement or mantenience system to have them in stock on a regular replacement parts shop, just on Mopar dealers, and nowdays at repro &/or performance market or used.
Slider caliper brackets are not really hard to get, Pin kind are nearly imposible thought ( and when they float on, on outrageous prices ).
Cass at Doctor dif is not the only source but also the Ramman. He uses to have both kind.
