You could try importing it to blender (the last beta version is very easy to work with). Then just create materials for it just if you are going to render it. Mark a seam and unwrap the model. Then bake the texture, there are very good tutorials for doing this on the internet. It's not so complicated. You can also create normalmaps for the model by using the texture baking method.
There are some great tutorial here:
http://www.blendtuts.comThere is still no texture baking tutorial on the website but the author is releasing a three part series about UVs & Textures. He only released now the part one but it will be enough to know how to unwrap.
Unwrapping the texture is the most complicated part (only complicated if the model is complex, but will be no problem for that bomb). I am now on an other computer and I don't have blender here, but you can find the texture baking button somewhere in one of the right panels (If you didn't change the layout). Look for it, I couldn't find a screenshot or tutorial to show you. I's easy to find.
If you don't have any experience with blender go first to this tutorial.
http://www.blendtuts.com/2010/06/blender-25-interface.htmlI also recommend you watching the materials tutorial for creating your material. Although it's very simple.
