If you would consider a used gun you could probably keep your purchase under $400.00 and maybe even end up with a real keeper. It may have slight "character" from normal use, but that kind of wear rarely affects shootabilty. (is that a word?)
Looking over the offerings on Gunbroker.com and GunsAmerica I see the prices are higher than the "under $400.00" I mentioned, but if you scour the classifieds and gun outlets and look over the used racks and the consignment racks you may find something that will please you.