AFAIK, they don't make stubby 800 MHz antennas with BNC connectors. I mean stubby as shorter than a quarter wave at 800 MHz.
There is the Comet CH-32 "Miracle Baby" stubby antenna, which is a little over an inch long, but it isn't really an 800 MHz specific antenna, but it will work there to some degree. Like AI42 said, an 800 MHz quarter wave is only about three inches long, and will likely work better than a stubby, unless the signals are strong to begin with.