You could shrink the gold leg texture down to the size of the gold reflection, make a selection around the gold parts of the leg, and on the reflection, apply alpha to anything that isn't in the selection (invert selection>delete), and then do the same for the silver. So you would have your leg texture with both silver and gold on it, plus a reflection texture which is split into gold and silver. That should work unless the leg textures are something like 512x256 and the reflection is 128x128 (height is greater on leg texture, where reflection has it equal). Of course,don't save your leg textures as when they are resized. I think there may also be a way to make masks with shaders, where it only gets applied onto the texture above it depending on the alpha levels of it but I'm not sure about that