Sounds like any one of a number of Husqvarna underlever models. They made them up until the mid 1940's. I believe they all have 2.5" chambers. They are well made shotguns, plain and serviceable. Yes most of them are choked very tight but a few days a Mike Orlen's and you can have the chokes opened or tubes installed for around a $100. ($50/barrel) plus the cost of choke tubes.
If it is in GOOD condition, no rust and most of the blue on the barrels and no cracks in the wood (walnut, you see replacement stocks in beech and elm) $400 doesn't seem out of line.
I shoot a pare of Husqvarna 51's(top lever) for duck hunting, the ugly one for saltwater and the nice bluing for fresh. I purchased a third beater for parts, don't know if I'll ever need any but it is nice to know there are a pair of locks nice and handy.
Here is a link to about a hundred of these for sale in various condition. It's where I picked up my parts gun.
http://www.simpsonltd.com/index.php?cPath=350_354_367&osCsid=b82906e51b66c69e1c5b415b19e3b9b7