I'm under the assumption that Guardian is the glass maker as well. Most of my searches have come up with nothing except a glass maker and local door shops that don't seem to have anything remotely like what I have.
Pictures

This is the aluminum channel that goes on the interior side, held in by several screws. It's the same for both top, left, and right sides.

This is the weatherstripping that goes on the bottom in between the two panels. It just pushes in.

This is the weatherstripping that goes on the top between the two panels. Again there are no fasteners for this one.

This is the weatherstripping that goes on either side of the casing again between the panels.