Yes. I had a S Asian riverscape tank a few years ago, and I wanted river gravel as opposed to sand this time, so I went to a local landscape supply that has rock, sand and gravel products. They happened to have a nice black-hued (it was a mix of black, buff, white, grey) gravel about the size of pea gravel. This would not work for many substrate fish, but as I wasn't intending these, just upper barbs, it worked quite well. The grains are very smooth, not rough. You want to ensure it is not calcareous (unless hard water fish are intended). They also carry river rock which is rounded granite pebbles of varying sizes that complements the gravel nicely. I did find a photo, not the best picture but this was the gravel.
