1664 - Thanks for that - so possibly large lyre removed (rather than crown) - and small lyre added.
I see John Rawlinson has The Royal Naval School of Music covered in his book on pages 283-285.
(Personal Distinctions: 350 Years of Royal Marines Uniforms and Insignia - for those interested it was Special Publication 41 of the Royal Marines Historical Society - see link
https://shop.nmrn.org.uk/collections...orical-society)