The first question that comes to mind is how much do you want to spend? Tanzania is probably best for what you want and a Buff hunt in the $10000/7 days area is a reality. Zimbabwe is another option.
I think that for a first timer you would be well served to use a quality Booking Agent. Finding one of these could be as hard as finding a PH though.
You should got to the SCI Convention in Reno the end of January. There you can meet a lot of Outfitters and agents and make your choices.
As far as the English Double is concerned you can pick one up in the 400 through 450 class for $10000 - 15000. Your best bet would be to deal with a known dealer and have a n inspection period that would allow for a knowledgable party to inspect it for you.
Prices may vary depending on where you are from.
-------------------- Lovu Zdar
Mick
A Man of Pleasure, Enterprise, Wit and Spirit Rare Books, Big Game Hunting, English Rifles, Fishing, Explosives, Chauvinism, Insensitivity, Public Drunkenness and Sloth, Champion of Lost and Unpopular Causes.