Martini-Henry Garrison Artillery Carbine (1878) help needed

Attachment 35520 Attachment 35528 Attachment 35522 Attachment 35521Is the Horse Head stamp and the 104 stamp the mark of the German 104 Artillery Regiment ? and is this a Martini-Henry Garrison Artillery Carbine ? i welcome all off your thoughts on this

Garrison units found the Mark I Carbine inadequate, as it did not have provisions to fix a bayonet
Addition of a bayonet lug. This came in the form of a new noseband with a lug on its right side
These Carbines are modified Martini-Henry Carbine Mark I's, and were somewhat of a stop-gap pattern until the Artillery Carbine Mark I was developed
Cleaning rod shortened to accommodate the newly implemented bayonet
The new noseband had to be repositioned lower down the weapon to allow the muzzle ring of the bayonet to fit over the muzzle
Utilizes a modified Snider-Enfield Yataghan sword bayonet (bushed to fit the smaller barrel diameter of the M-H)