Right, I have been reliably informed that just replacing the textures is not a good idea.
So here are the same rock models, all reskinned. Unzip it into your tf/ directory, and the new models and materials will be installed under props_forest/rock001 to 007.
Alpine Rocks The props_mining rocks, reskinned for alpine environments.
This is a derivative work of Valve's rock models and skins. I disclaim all rights in them. You may only use them with under the same conditions as other content from the Source SDK. You may use and pakrat these reskinned models in any TF2 map you make (whether a contest entry or not).