Generalwar,

Gir forest is the only place you can find Asiatic lions. Most of Gir forest was in Junagadh Territory but Gir extended into other states as well and Gondal was one of them. In 1936 a ban was called on the hunting of lions for sake of conservation. The Maharajah of Gondal refused to cooperate and to surrender his right to shoot lions, so there is good chance that rifle shot quite a few lions there.

In the picture below you can see the skin of a zebra at one of the palaces of Gondal, so I am sure the Gondal household paid a visit to Africa as well.

P.S The engraving on your rifle looks like Asiatic lions to me.