I've heard of good results with fairly simple Texas flag jerseys, (even outside Texas) but can't seem to find one in a full-zip style. Closest seems to be the Canari "Texas Retro" which just doesn't have the long-range recognizability of a simple flag or large Texas silhouette like the Voler and Primal Wear ones that are only 3/4 zip. (Sometimes after a long ride, an old shoulder injury hurts to the point where pulling a jersey over my head is painful-to-near-impossible.)
You could also try this one:
