Did I miss the part where you can't wear a tuckable holster? I made mine, it's a hybrid of kydex and leather, and they're all over the internet. Crossbreed is awesome, Comp-Tac is another. It's 110 today, and I'm wearing it under slacks and a tucked in button up shirt, with an A-shirt under. You just have to practice your draw with grabbing your shirt out of the way when it's tucked in front of your holster.
This is mine, with my glock 26. I also carry a browning hi-power, as easily. I'm 5'10, 175lbs.
There's also alot to dressing around your gun. If your pants have a little bit of wiggle room, you'll be fine. You don't want em "suck it in to button em" tight, because your holster adds like 2" to your waistband. Mine tucks well into my love handle, and my shirt has a little stretch room.
I wouldn't bother with pocket carry, when you already have the 19! The 19 is a fine carry gun. Carry away from work for a while and get comfortable.