.Map :: MoHAA Mapping

Hey, I'm looking for somone who could make a model (or make it out of brushes) of a farm silo...I am looking for it to be about 400-500 high with no entrance in the bottom but one entrance on either side of the hemisphere at the top... It would need to have a platform inside with which someone would be able to sit and snipe...

Reply if you are interested in makeing it or could help me make one, I have tried but they look like crap, any advice would be helpful...

Thanks