Thanks to all. Here's my plan for now. But a 6 foot or so of 6x6 or4x8 wood. Put it in the attic, on top of the joists, perpendicular to them, right above the T beam that holds the hoist. Put 3/8" or 1/2" threaded rods through the wood piece, down and to bolt some metal brace underneath the T beam to these rods. That, I think, could easily hold a ton, which is more than I need.
The wood piece above the joists would span something like 5 joists.i