Any of the below, & others, offered the stepped lock variant:

Karoly Kiszela Pesten - Pukar

Anton Vincenz Lebeda Prag

Anton Mulacz Wien - Bchsenmacher

Jozsef Kirner, Jr. Pesten - Pukar

Karol L. Werlik Teschen/Cieszynie - Rusznikarz

Antoni Werlik

Karol Spiegel Teschen/Cieszynie - Rusznikarz

I would guess he sourced Kirner or Lebeda, maybe Mulacz.

If you divorce the tubeset from the frame, marks there, if any, may point to the actual maker. Johann Hnl/Haenel of Willomitz/Vilmov more than likely was a Country Gunsmith that was more or a retailer/firearms merchant than a maker.

Steve is your Anton Vincenz Lebeda example cased and in the high 85xx serial number range?

Kind Regards,

Raimey
rse