I just line the underside of my carpenter's square with another, reasonably thin, leather. Flesh side down, since it'll have more static friction that way. Just make sure it isn't some heavily saturated stuff that'll leave dye or oil on your work piece (experience is an excellent teacher).
Bob Douglas is indeed still making tools! Just got a pair of his “slim” awl blades. Paired with the Barry King “medium” handle with the flat on it results in the classically fantastic combo. Goes right through leather and straight into my finger with frightening ease!