Sourcing Triple-Glazed Insulated Glass Units

I understand there are many discussions about sources for triple-pane windows, but my focus is on insulated glass units (IGUs) specifically. We have a large window measuring approximately 11'10" x 6'4", which comprises 12 panes and is essentially a site-built wood frame. It is the last window in our house that still needs replacement. The wood is deteriorating, and given the presence of lead paint, we plan to construct a new frame. We've already reinforced the area around the window, so it no longer plays a structural role, but we appreciate its aesthetic appeal. Therefore, we want to create a new frame and install IGUs that match or exceed the energy performance of the other windows in our home, especially considering the large glass area.

Currently, I'm exploring site-built wood framing combined with a hardware and seal system from Stabalux (Stabalux), which can support IGUs up to 2.5 inches thick. However, I cannot finalize the specifications or pricing for this system until I determine the required thickness, weight, and sightline coverage of the IGUs. Unfortunately, I'm facing challenges in finding a source for triple-pane IGUs.

While Cardinal, a major manufacturer, seems to only sell to window manufacturers, my experience with Alpen was equally frustrating. After a month of discussions, I was informed that they only sell to certified glaziers. Searching for glaziers in my area around Cleveland, OH, yields either auto-glass replacement companies or standard residential window replacement services like Pella, Universal Windows Direct, or Bob's Budget Vinyl Windows.

I do have a conversation scheduled with Litezone on Monday, so I am hopeful about that prospect. However, both Litezone and Alpen employ suspended film technology, which lacks the established track record of traditional glass. Litezone also does not perform argon filling, claiming that this benefits performance due to no risk of argon leakage over time. While that may be valid, is it merely a roundabout way of stating that their seals are not reliable?

Therefore, I am reaching out to see if anyone can recommend a reliable source for quality triple-pane IGUs.