A833 NP A body trans ID help & intro.

OLD BOLT AND KNUCKLE BUSTER NEWBIE HERE. Been wrenching since 1963. Bought a new 1968 Roadrunner 383 4 speed when I was in the Army, followed by a 1970 Duster 340 4 speed car....of course I wish I still had them !!! Did a resto 70 Duster 4 speed 25 years ago, but divorce forced sale. Last 25 years I got into Super Bikes, but recently bought and all original 1973 Duster Twister Cali car, 318 3 speed. Just picked up a NP A833, A body 4 speed trans and need help ID'ing this little gem. Body # H3 over 0.99129 and no #'s on pad. Side cover #C? 95884 followed by BIG letter Z. casting tag X11. Casting #'s are hard to read. I'm thinking this may be a "replacement" trans? There's mismatched bolts on the side cover, so someone been inside. Ball detent type. Opened it up and lube is very clean, gears in great shape, and nice even wear pattern on everything. Turns and bench shifts smooth.