HorseApples, I took some measurements.
The handle is 1 3/8" wide and tapers to 9/16" wide at the tips.
The handle tapers from 3/4" thick to 5/8" thick where it noticeably starts to bend. These thicknesses should be some close numbers to gauge off off of, but every piece of wood is different, so error on the thick side and work her down slow. Hope this helps.