If you are looking to do a 12 bore I would look at a Fox. For what you want one of the late Savage guns is fine or you might pickup a early A grade that has no finish left for about the same money. Between the two there must be 50,000 guns so one more or less is no great loss and these are not the hot collectable guns like higher grades or small bores are these days. Past that your only limit is time and money and if your have enough money then you can make almost anything that you want.
Just remember to find a working gun first, do the metal work and bore-choke work, then the stocking, then the finishing of metal and wood. There is a logical progression to a remaking of a gun and it is too easy to get the order wrong. Too easy to get nice looking wood on a gun and then loose interst in the total project. But to me ugly guns with nice wood still look half ass done.