Why not buy your own barometer? You should be able to pick one up in a second-hand shop. The mercury ones are approaching becoming illegal bacause of the mercury contained in them, and as people worry about such things, the value of these will probably drop. They are, however difficult to set up and best left to specialists. The other type is the aneroid barometer, which looks like a wooden-cased clock. Try auction sites, local auctioneers, S/H shops, etc., check it works by putting in a clear plastic bag, and blowing into the bag while watching the indicator.
philtherod