The "Prince of Whales" marking is not consistent with any marking on any Dunhill I've ever researched. I tried to look up yours specifically, and nothing has come up. Every Dunhill, it seems, is marked with "Dunhill" and the color, shape and year codes should also be visible. Unfortunately, it doesn't look like you have a Dunhill pipe. It's possible that the stem is from a Dunhill pipe, but there's nothing guaranteeing that someone didn't rip off the tell-tale white spot in order to attract a buyer, either.
Hopefully someone with more knowledge than I comes along and proves me wrong!
Oh, and welcome to the forums! :
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