http://www.ebay.com/itm/400992609457
These chaps were made by Vanson Leathers of Boston, MA. They are made of heavyweight cowhide with stitched leather bones. They have single piece legs with full length zippers, a seven snap front, and an adjustable lace up back. Vanson sizes their chaps by thigh size, these are tagged a 23″ thigh.

Minimum waist (side to side): 17″, doubled = 34″. Remember that this measurement should be taken overtop your pants, and that with the lace up back, these can adjust as large as needed.
Outseam: 41″