Well...
The product was officially dropped in 10/31/2018. We're a master distributor for their products. I checked my inventory and we don't have any here. I also checked Mannington's inventory and they don't have any either.
I'll tell ya a little story about how this kind of thing works in our industry....
Typically twice a year a manufacturer such as Mannington will have a new product introduction and also at the same time list any products that are being dropped. Our national trade show for the industry, prior to Covid, was held in Las Vegas at the end of January every year. At that event any remaining inventory would be blown out to "specials" dealers who buy discontinued perfects, mill trials, off goods, and rems (roll ends on sheet vinyl & carpet) at ridiculously low prices. These specials dealers will literally buy truckloads of this type of product and then sell it cash-and-carry or over the internet for a crazy price. So, that means any remaining inventory on this product would have been blown out at Surfaces (our trade show) in 2019. As a master distributor, we do the same things with remaining dropped inventory at our regional shows for our dealer base. Basically that means that your chances of finding this are slim and none and slim left town. Also, if you did find it, it's dye lotted material so it may not be a perfect match to what you already have.
In this particular case, it's probably even a greater probability that none exists anymore because this was not just a case of a dropped sku. This was also the point in time when Mannington changed the entire Adura line and converted over to the current offering and format. Everything about the product changed. Mannington would have begun to "work down" their inventory knowing they were changing formats and so when this dropped less material would have been on hand to begin with.
Your only chance at this point would be if an specials dealer who sells on the internet might have it. However, most of those guys don't sit on inventory very long. It's all about "turn & burn" with those guys.
I wish you luck, but I'm afraid you're probably fighting a losing battle.