I think the Sig is under 300$ and well made and very similar to their combat guns.

You could find a used 1911 clone and a .22 conversion kit. Then you would have both a cheap plinker and a classic American .45 for home defence while keeping to one gun.

I would also consider a 12 gauge pump as a much better home defence weapon than any handgun. A used Mossberg is only a couple hundred and is used by the army in Iraq.