Steel backed split piston pin bushes are used in diesel engines.
How would one of those work for a T/S bush on a bsa? They come un-sized with about .015" for machining.
This is of course assuming there is one of the right size.
These would be VP10 as a Vandervell made Bush or SY if a Glacier bush. Chemically the same, Vandervell cast on steel, Glacier sintered onto steel. Difficulty is finding the right sized bush, Perkins or Cummins would be a good start. The same bronze is used by most steel backed bronze bush makers. Just stay clear of modern car engines which are lead free and the bronze suffers.
Glacier Industrial Bearings do SY bushes in imperial sizes.