Here is an image of a stamp featuring a portrait of Norwegian composer and pianist Edvard Grieg (1843-1907), and depicting fanciful creatures and the score for Solveig's Song from Peer Gynt, Op. 23, designed and engraved by French artist Pierre Albuisson (1952- ), and issued by Monaco on December 10, 1993 to commemorate the 150th anniversary of the composer's birth, Scott No. 1886, plus an image of a photograph of Edvard Grieg in 1888, and a YouTube link to a recording of Solveig's Song by the Slovak Philharmonic Orchestra.
Here is an image of a stamp featuring a portrait of Austrian composer Carl Michael Ziehrer (1843-1922) and depicting a partial score from one of his compositions, designed by Adalbert Pilch (1917-2004), engraved by Rudolf Toth (1918-2009), and issued by Austria on November 14, 1972 to commemorate the 50th anniversary of the composer's death, Scott No. 932, plus an image of the photograph of Carl Michael Ziehrer which was may have been a model (sans the martial attire) for this stamp's design, and a YouTube link to a recording of Ziehrer's lively waltz In lauschiger Nacht, Op. 488, (c. 1905), performed by the Berliner Symphoniker, Robert Stolz conducting.
Here is an image of a stamp featuring a portrait of Lithuanian composer, painter and writer Mikalojus Konstantinas Chiurlionis (1875-1911), and depicting waves and a lighthouse, designed by K. Iodikaitis, combined engraved by Vladimr Smirnov and photogravure, and issued by Russia (USSR) on August 20, 1975 to commemorate the composer's birth centenary, Scott No. 4357, Zagorski No. 4442, plus an image of a photograph of the composer, and a YouTube link to a recording of M. K. Chiurlionis's symphonic poem entitled Jura ("The Sea").
Here is an image of an airmail stamp depicting a woman in a diaphanous gown dancing, designed after a vintage Oscar Brandstetter, Leipzig poster promoting a performance in Germany of the waltz Sobre las Olas ("Over the Waves," 1988), the best known work by Mexican composer Juventino Rosas (1868-1894), printed by lithography, and issued by Mexico on October 16, 1972 to publicize the 28th Congress of the International Confederation of Societies of Authors and Composers, held in Mexico City, October 16-21, Scott No. C407, plus a YouTube link to a recording of Sobre las Olas, a tune with which everyone here "of a certain age" will surely be familiar.