Its probably more fun searching all of those out of the way gun shops and pawn shops to find that perfect gun / at the right price - than it is actually buying the gun ...... But trust me, there will be another gun out there for you, when you least expect to find it.
I was in a pawn shop yesterday - and of all things, he had a Win model 42 pump gun ( .410 ) pre-war, in Deluxe Grade. To my limited understanding of Winchester pump guns - the Win model 12 pump guns were made in 12, 16, 20 and 28 ga / then they made the model 42 in .410 ... and there may be other differences, I don't know..... He wants $ 3,600 for it / and its probably worth it. I'm not a Win pump gun expert / frankly I don't like them much at all - but to see that gun - in a pawn shop was a treat. If I wanted to add a couple more pump guns for the grandkids to shoot - in 28ga or .410 , I would probably just buy the BPS Hunter models for about $ 500.
Personally, I think the BPS Hunter is such a good buy right now / for a versatile field gun / first gun for a young shooter - 28" barrel, 3 chokes, etc - that I'm actually considering ordering about a dozen of them in 12ga and putting them away for the grandkids when they each turn 16 or so .... and even if some of the kids didn't want them down the road, they'd always be easy to sell as "new in box". My biggest issue is where to store a dozen shotguns in boxes - I don't have the room in my safe .... or room in my shop for a 2nd safe ... Anyway, take care - and have fun with your search.