Here in Britain I have just finished reading a review of the Haenel Jaeger 9, which is a new Kipplauf rifle like an over-under shotgun but with just one barrel. It weighs 2.30 kilogrammes, which is 5 pounds 1 ounce in Imperial units. Calibre is .308 Winchester, which will be ample, but there are other options.
The British distributor is Viking Arms: see www.vikingarms.com

It looks really sexy!

HB