Need Help Recreating A Moccasin Stitch

[smithmeade]

Hello! I am trying to play around with different techniques for constructing moccasins but can find very little info online about different approaches. Hopefully one of you leather pros can help... I've done the traditional Inca boot style (first image), but am trying to figure out how to do something like the double-stitch in the other two images attached. It looks like a variation on the traditional Inca style? I know the stitches I'm looking to recreate were done in Mexico, if that gives any clue.

Any insights, including some good sources for moccasin stitching in general, will be appreciated.

Thanks!