Truthfully a .300 will probably increase your chances of taking game, but simply killing a lot of animals doesn't necessarily equate to success.

I would think that the 9.3 is fine, as in it will surely kill, but perhaps the thing to do is to make sure the outfitter knows your shooting capabilities and personal hunting preferences.

If it was me I'd take the double and leave the scope at home.

Just my 2 cents - nothing more.

Best of luck and post pictures when you get back.