Where did you try all that by the way? There used to be somewhere near me that did an African mixed grill like that, have to say I wasn't impressed by kudu!
a mate in suffolk used to get it for me from one of the butchers down his way, cant remember where exactly but he used to live in lowestoft.
as for the goat, its very popular in west indian cooking so see if there is a west indian shop near you. we used to castrate the billy kids on the smallholding, then put in the freezer at a few months old. very tasty!
I know a good few west indian lads in Bristol (don't ask me how i know them