I could only find it in sheet goods. The sheet goods wouldn't be all that bad to install, but to double coat all those edges with "edge sealer" like the manufacturer suggests, would be a nightmare with all the laps and cuts you are going to have with a 7" exposure panel.I haven't installed mdo lap, but we tear it off houses all the time. Honestly, I don't think they make it anymore.
On a side note, mdox is great stuff in sheet form. I've wrapped a few front porch columns with it, and they hold up to the weather. I 45 rip them with the shop saw, assemble on site.