Cant be sure, but it seems like it has the Greener lockup system.
If the top lever pivot is behind the rear face of the action, it is likely a Greener lockup.
Also, the "Treble Lockfast " is a Greener trademark I believe.
Many "makers" bought guns and finished them, Cl Bros included.


Dumb, but learning...Prof Em, BSc(ME), CAE (FYI)