Ken
Powell's Number 1 Patent "the lifter" is ambidextrous as far as opening is concerned. Trigger alteration would be relatively simple.
Hammer centerfire lifters were made from 1867 into the 1890s.
Most are Damascus but some have steel barrels. Boxlocks are relatively easy to find - but sidelocks are scarce.
These are my specialty - so if you want more info, just let me know.

www.powellspatent.com