Likely it came from china. You can get the hookup on it if you want a couple of shipping containers of it.
Locally, you might check with Macklanburg-Duncan. I doubt they make that exact profile but might be able to point you in the right direction.
Whatever the original application was is going to be the cheapest source. They already bought the majority of a shipment.
I first thought store fronts and windows, but there is too much radiused surface. At least for the US, maybe in Europe.