gjw:
In my youth, I was subject to may lessons from parents, grandparents, teachers and other adults that cared to pass on their lessons to me. Some I took to heart and have been the better man for having remembered. Others, I passed off as not worth my time.
Now that I am old man, it is so easy to think that what I say is wise and worthy of recognition. Perhaps this is true and perhaps it is just the ego of a man of old age, that wishes youth to learn and profit.
I will venture to say, to you, that what KYJon has stated is so vitally important in the quest of a shotgun, that to ignore his sage advice is to play the fool.
BUY THE GUN !!!! The gun, either in your hand or in the hand of an agreeing smith of competence. To do otherwise is to play a game that you are certain to lose.
I hope that you are sincere in asking for guidance. If so, you have it here. If not, have a nice day.
Best,
John