for bead leaks, try roof flashing tar, or windshield urethane on the beads.
i used roof flashing tar. worked pretty well. i have no beadlocks, and i never burped air till i was at 3lbs, and pushing hard into a hillside to right a flop. it never lost a bead. i sheared a valve stem at the mounds, and the tire stayed on the rim with zero air. it was a bitch to remove the tire to fix the stem though.
for sidewall pin holes you might try scuffing the inside of the tire and smearing it with vulcanizing glue. it kinda melts into the rubber. kinda like model glue does to a plastic model. that is assuming you can find where the air is escaping from. good luck