Hi,
Here's the data:
The gun is a two-part affair, thus providing means to cover two versions
Frame: 2850, marked on front.
Receiver and barrel: 11910 marked on barrel w. crown/N underneath it.
standing Crown-N and 10 on left side of the receiver, KOL on the right side.
Takedown-lever and sideplate marked '11' in commercial style (underneath).
Grips marked as discussed earlier. Both marked 2850. Left with C-type mark lying flat above it, Right with GS mark above it.
Sear bar also marked with GS on top (only visible after removal).
Brass side plate reads 'St. Inf. XI. 28'.