Your starting SG/SF have staminas of 67 and 68, respectively. Problem solved.
Those guys are pretty good players (minus their staminas). You just need to make sure you don't have two starters with sub 75 stamina when running press otherwise they're going to get tired, plain and simple.
I used to pay extremely close attention to how jsajsa built his teams when he ran press at D3, as he was probably the best D3 coach to ever play this game. His teams always had team staminas in the high 70's to start and the only time he would R/S a kid was when that kid was gonna be an absolute D3 monster, and even then if he thought it hurt his rotation for a year he'd be hesitant to do it.