HI shahed
If the periscope mod use's DAT files you will need to extact the tga files from my skin Dat files and place them inside the periscope mods DAT files use the chessmaster extact tool thats at the link above.
I have done a number of camo skins check this link
sub skins
you may need to read through the link to find where to get the skins.
I have also got some more skins comming out soon.