Actually, the Carcano is not a Mannlicher Schoenauer, "revamped" or otherwise.
The Carcano is an Italian made arm that feeds from an en bloc 'clip' (the Mannlicher Packet Loading System). It was designed in 1890 by Salvatore Carcano as the Modello 1891 and entered production in 1892 whereas the MS was introduced at the 1900 Paris World's Fair. Carcano had been greatly influenced by the 'Commission' 1888 that was the common ancestor of both Mannlicher Schoenauer and Mauser 98.
The 'Greek' Y1903 is a Mannlicher Schoenauer as it incorporates Otto Schoenauer's rotary magazine.
A firearm without the Schoenauer rotary magazine cannot be a Mannlicher Schoenauer, and all genuine MS, military and civilian, were produced at Steyr, Austria (though the Y1903/27 were allegedly assembled in Italy).
Carcano:
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Oswald's rifle - not a Mannlicher
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Carcano En Bloc
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Schoenauer magazine
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