I like these guys and they are getting more into 3d scanned surfaces and substances. The textures you want to look for are the seamless ones. https://www.textures.com/
If you still have issues with tiling the textures I think another method would be to purchase a substance of the wood texture you need. You can download the free substance player here:https://www.allegorithmic.com/products/substance-player
Substance player will allow you to modify the textures scale, color, and resolution, then you can export the image maps for both the metal and roughness PBR methods up to 4K resolution. The maps can be plugged into Octane, and because they are procedural, they will be different no matter what resolution you output them at.