These days, stamps from Japan is one of my favorite searches on EBay.
I couldn’t resist this beautiful postcard and stamp from 1921 that was offered for just a few dollars.

Issued Apr. 20, 1921
Perf. 13 x 13½ | Uncoated paper | Engraved
164 A47 3 sen violet-brown Ministry of Communications Building, Tokyo
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Translation of the Japanese text on the postage stamp:
At the top 貳拾五年紀念奉祝 (Nijūgo-nen Kinen Hōshuku) – “50th Year Commemorative Celebration”
At the bottom 日本郵便 (Nihon Yūbin) – “Japan Post”
三銭 (San sen) – “3 Sen” (Sen is a sub-unit of the yen, used until 1953. Following World War II, the yen lost much of its pre-war value as Japan faced a debt crisis and hyperinflation)
Bottom right: 大日本帝國政府印刷局製造 (Dai Nippon Teikoku Seifu Insatsu-kyoku Seizō) – “Manufactured by the Printing Bureau of the Government of the Empire of Japan”
[Sources: stampworld.com, Scott Standard Postage Stamp Catalogue 2017, Vol. 4, Chat GPT]