I can't really help, because my 743 doesn't have ad glass in it yet. It's my understanding that you put glass in the same way you would put glass in most other pumps -- using rubber with a channel on each side. What's different about the 743 is the shape of the ad glass, and I don't know of any source for that. I'm planning to find a piece of ad glass that is just a little too big, then cutting it down to size. Of course, with those those strange angles and round corners, we can't use the score-and-snap method. Perhaps cutting with diamond tools in a Dremel would work. I hope someone chimes in who has put ad glass in one of these pumps before.