There's a fella in the Facebook V8 Ranger groups on Facebook that has carried on the work of Gumby (12" Sport Trac) and Tee-Rev (13" Cobra) with big brake kits. Name is Chris Salmon, he posts in one of the V8 Ranger swap groups.
I don't know if this link to his groups profile will work. His business page is is
S&S Engineering LLC.
He offers Gumby's bracket setup almost exact, nice tig welded bracket with zinc plating. I think they normally run $165, IIRC he said something about a sale on the last sets he had in stock the other day. Going forward, they'll be done like group buy, once he has enough sells he'll build and sell the kits. If you can live with the 12" brakes I'd get in contact asap.
He's also modernized Tee-Rev's kit to use 4 piston Brembo calipers from a Cadillaic ATS with the same 13" Cobra rotors. Just got confirmation that these will still fit under most 17" wheels like the Cobra kits, in case that was a concern for you. Last batch he posted for $475 shipped, don't know if he has any left.
If I were starting over with nothing on my 85 I'd probably go with the Sport Trac kit and be happy. It would still be larger and better braking than 90% of other 83-97 Rangers and dual pistons unlike the 83-92 Rangers. I've already got Tee-Rev's Cobra kit that I bought years ago for my last Ranger sitting on the shelf, along with most all the parts needed for install. Doing it over now, I don't think I could justify the added cost of the 13" brakes regardless of if it was the Cobra or Cadillaic calipers. If it's just for improved braking, I think that the 12" would be plenty. If it's for looks and street credit, it might actually be worth it.