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Ross rifle was created in 1903.
They used the British Lee Enfield SMLE Mk III in .303 caliber. For a bolt-action rifle it was capable of being fired very quickly, although it was not as powerful as its opponent, the Mauser 98 rifle used by the Germans and Turks. [The Canadians in World War 1 were less fortunate than the diggers, using their own rifle called the Ross which was not as good.] The Lee Enfield was also standard issue to British and Commonwealth armies in World War 2, Korea, and Malaysia.
Ross Lowis Mangles died on 1905-02-28.
Jonathan Ross - senator - died on 1905-02-23.
Stephen Ross Harris died on 1905-01-15.
Canada
In the age of the Internet a simple search with terms like "Ross Rifle" or "Ross Rifle parts" will turn up various dealers. Including your address, if you are into bricks and mortar stores to shop at will find local dealers.
ross rifle
Sir Charles Henry Augustus Frederick Lockhart Ross
Canadian manufactured military firearms have typically been firearms with origins in other countries which were manufactured under licence in Canada (e.g., the Short Magazine Lee-Enfield Rifle, the C1 Self Loading Rifle [based on the British L1A1, itself based on the FN FAL], variants of the M16 and M4 manufactured as the C7 and C8). One notable exception to this was the Ross rifle, which went into production in 1905. It used a straight pull bolt, and fired the British 7.7x56R (.303) cartridge. However, it was found to be problematic in the mud during WWI, and was quickly replaced by the Lee-Enfield rifle, although it remained popular with snipers and sharpshooters.
Ask a gunsmith for help.