I don't have a manual either, but if it's six bolts (two on each side, one top and one bottom) then it's probably a standard SAE six bolt pad. If so, they're really nothing special.
Center to center, top bolt to bottom bolt is roughly five and a half inches, and side to side is roughly four and one eighth... Lots of makers out there, but they typically come in this style made of heavier gauge metal, or a lighter gauge that has the outer perimeter rolled up to prevent warping when you bolt it down. Lots of pickup transmissions and transfer cases had them, a local wrecking yard should be able to find a core to snag one off of, or as mentioned, custom vehicle upfitters tend to have a lot of them in the scrap metal heap, or even brand new they're pretty inexpensive.