A drift/punch works fine as well. Take the sight out left to right (direction of ejection port), tap in the new one right to left. If it's not going anywhere, take a very little bit of material off the bottom of the sight with a fine file or sandpaper and try again.
Is the press for rent? Is the $20-30 you quoted to rent the press or to have Dan install the sights?
I put a new sight on mine yesterday. It was just moving nowhere. I put super fine sand paper to the bottom of the front sight a tiny bit at a time and got it moving in smooth with no damage. I also ground down the drift to fit in the groove perfectly and it went much better this time.
I had to dremel a relief cut into the stock sight to get it out of the 9. These things are ridiculously tight.