Main difference is the aluminum frame that every post war P.1 or P.38 that I've seen has had. OP didn't state condition of those priced at $419, but if average, the price is also about average. Nice ones sell for more. There are tons of these around, most are common surplus guns, not rare. In addition to several war-time P.38's, I've owned probably half a dozen post war P.1 and P.38 (yes, some were so marked). None were particular tack-drivers, more often sprayers, only one post war gun was above average in that department.
Probably a wise decision. They were pretty gee-whiz in their day but now there are lots better 9mm pistols. Once you get tired of it, they aren't fast sellers there are so many of them. I have one byf 43 that I've kept mainly for historical reasons. Yes, it will shoot. But I've kept it because it's a Russian capture gun, no question it saw use on the Eastern Front.