Looking for a Damascus Steel Tileable Pattern

[Midgardsormr]

After Effects has some really nice fractal noise effects that Photoshop lacks. This looks like the "Swirly" setting. But you've managed to pretty well replicate the look with your technique. You might also see what you can do with Posterize and Find Edges on your swirls.

[mthomas768]

You might also try re-adding your original steel image as a low opacity overlay layer on top of your swirl pattern to get a little bit of grit into your pattern. You can also deal with seamless edges using the Layer / Transform / Offset to 'slide' the edges to the center so you can work across them. It means working on only sections of the image at a time, but you can get seamless results this way.

Here's a quick trial I made using your technique.