Mamluks are a vanilla unit so unless SS specifically changes a file for it, it doesn't have to be included in the SS install (the game just uses the vanilla file). So to get their unit card pic you're gonna have to unpack it from the vanilla files using the unpacking tool in M2TW\tools\unpacker.
However, it's not wise to unpack everything as this can cause problems in running your game. So when I need to unpack stuff, I tell the program to put the unpacked files into another directory and I specify to only get the files I need. Use the following in a .bat file to run the unpacker program to do this:
Code:
unpacker.exe --source=..\..\packs\*.pack --destination=c:\packs\text\ --filter=*.tga --verbosity=1