My current PZ30B says Made in Japan, and it was bought directly from China.
My Mikuni VM26 said "Mikuni Japan" also from China.
Fact: They can make it say anything they want to, doesn't mean it's true.
Second Fact: A real PZ27 framed carburetor has a gusset between the slide tower and rear flange. The "PZ30" sold on the internet is a copy of the 27 with an enlarged throat, but it is missing said gusset. Picture:
https://www.jetsrus.com/photos/photo_JRU-0315.jpg
Final Fact: Keihin never made a 30mm PZ carburetor. The largest official Keihin PZ production carb was the PZ27. The PZ30 is a modified clone made under license by a couple of chinese companies for their clone bikes, and a few others without a license because they can.
Real Keihin PZ carbs use 99101-116 main jets and N424-74C slow jets. Clones don't use either of those. Often using the 393 main jet instead of the 116, and the 21 variant of the slow jet