We found a rolled sleeping mat, solid type, in the labyrinth of tracks on the Flat Rock Plain (Between the two high points heading west above Granite Beach)
That stretch is so fun. There nothing quite like the track braiding out into 50 different ones. I found a hat caught at head height, and then had it torn off my head 20m later.
Not my mat though, good luck.
Men wanted for hazardous journey. Low wages, bitter cold, long hours of complete darkness. Safe return doubtful.