(This is listed as a boy's costume, though there's no reason a man couldn't wear it as well.)
The 1887 description:
RICHARD I., COEUR DE LION. In a maroon velvet tunic trimmed with gold lace, three lions couchant embroidered in gold on the breast; white silk tights; velvet trunks; gold and satin shoes; jewelled belt, sword, and dagger.
The 1880 version differs only in making the lions courant (running) instead of couchant (lying down). Historically, Richard I appears to have used a device with the three lions passant gardant (striding, facing toward the viewer.)
Sources:
Holt, Ardern. Fancy Dresses Described, 2nd Edition, Illustrated. London: Debenham & Freebody, 1880.
Holt, Ardern. Fancy Dresses Described, 5th Edition. London: Debenham & Freebody, 1887.