The combination of antennas suggested above are not overkill in your situation, I'd use the same combination myself.
It sounds like you may need to consider other mounting options such as a roof mounted tripod or ground mounted push-up mast. If you have a gable end, an eve bracket may work. Finally, how about a chimney mount kit?
Here's one of the most comprehensive selections of masts and mounting accessories I've found in one place.
http://www.3starinc.com/