The number of Model 1876 muskets that were fitted with a sword bayonet is currently unknown but the numbers appear to be very small.  

It is believed that the sword bayonets for the Model 1873 and Model 1876 are very similar but not interchangeable due to the size of the muzzle ring diameter.  The heavier Model 1876 has an 18 millimeter muzzle and the Model 1873 has a 17.5 millimeter muzzle.  But, more research is needed to verify.

I have been told by a knowledgeable Winchester collector that the Winchester Model 1876 musket for the Hawaiian Citizen Guard is different from the standard Winchester Model 1876 musket and that the bayonets may not be interchangeable.  

There are online pictures showing a rifle with a brass hilted sword bayonet labeled as Winchester Model 1876 Hawaiian Citizen Guard. The bayonet is like the Model 1873 bayonets without the hand guard. 

Information on the so-called standard musket is still being looked for.    

Bayonet Variations