John,

the text says "In addition to the firearms currently shown with the vehicle, the Tiger Car is accompanied by an ammo box......". So that's all included in the auction.
It's funny that Bonhams have not included a detail despription or at least a list of the guns. After all, they do have their gun experts.

The Howdah pistol appears to be a percussion muzzleloader.
Then I see a long-barrelled over-under shotgun, a side-by-side shotgun, a single-barrel shotgun (probably pump action) and a rifle, probably military, probably large caliber, with a military sling. It would be interesting to know if these come from the maharadja's arsenal or are later additions.

fuhrmann