I'm fairly sure all of those should fit your Buckmark as well; the 5.5 Target has an even larger diameter bull barrel, full-length optical rail, and a very different front sight. THAT'S the model that none of the replacement sights will fit; your Buckmark shares the barrel length with that model, but not much else.
Here's a link to Browning's historic webpage for the 5.5 Target model:
“It is foolish and wrong to mourn the men who died. Rather, we should thank God that such men lived.” -- George S. Patton
Last edited by DJ Niner; 04-20-2013 at 02:55..