I can't think of any instructional material but if you combine Roy Nichols and Django Reinhardt you be on your way. Here's some old school recommended listening if you can still find 'em:
Biller and Wakefield
The Hot Guitars of BIller and Wakefield
www.hightone.com
Dale Watson's first two Hightone CD's
Cheatin' Heart Attack and Blessed or Damned
Herb Steiner's Texas Dance Time
www.herbsteinermusic.com
Travis County Pickin'
His 3 cuts are great, the whole album is nothing but Western Swing, Chicken' Pickin' instrumentals
www.musicroom.org (there may still be copies)
He plays on a lot of local's records so you might check
www.texasmusicroundup.com and do a search on hig name, that might help.
PP