Finnish Ulaani Carbine-Ulaanikaribiinit
 
 

You can only see it very faintly in this picture, but the stock is marked on the butt with an S and the serial number.  Receiver has been scrubbed and is marked with an S and the barrel is marked 1915

Front sight is from a M91 instead of the reported wing protector type and the rear sight is marked 4,6,8,10,12

This mark is on the left rear of the stock

Pictures furnished by Ken Buch
This is a Ulaani that he imported from Finland
Thanks for sharing Ken