Wish i had the P13, I have examples of two different made 1907's and the P1888 but the 13 has eluded me so far.

My 88 is marked SAS SAR in a cross, both initials being for the South African Railroads in 1942

The 07's are marked SAR and AECO.

All these blades I understand are even hard to find in South Africa

You can see my examples on the south African page on BAyonet Collection Presentation