Meyer's 1891 Spanish carbine posted on this forum and pictured in MMROTW(5) p. The two 1891 Spanish carbines that I have pictures of the cocking piece show it marked with a 'B' in circle, otherwise it seems to be like the early type 1891 Argentine cocking piece.
I know that the 1891 Spanish Carbines (1891 Argentine Pattern) used a bolt sleeve and safety flag with Turkish markings and presumably left over from the Mauser Turkish production run. Were the cocking pieces on all three of these rifles the same?