Search was a challenge because the video that used it played it at half-speed, but after 8+ (!) years I finally discovered the song. In fact it wasn't from a Miyazaki film but was written by an obscure Japanese musician, presumably a royalty-free one:
SAMURAI SPIRITS - Hakone (https://www.youtube.com/watch?v=u_70LeOlRWA).
Finally solved, but can't find a way to close my own post.
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ZloyBritvich
Mr. Pink feat. Paloma - Club Bizarre (Mr. Pink Fresh Redub Mix)
https://vocaroo.com/16cgTKSxJLUv
Il y a 604 jours
ZloyBritvich
Il y a 615 jours
ZloyBritvich
Il y a 715 jours
ZloyBritvich
Il y a 723 jours
locchox
Il y a 879 jours
chrisgo
(good luck..)
Il y a 879 jours
zozinhoe
Il y a 880 jours