I wouldn't go to Namibia without harvesting a Hartsmann's Mt. Zebra.
Yes this as there is always the chance they may not be importable in the future, but not likely. The Hartman's is native to Namibia and a small portion of SA only. I really like their stripe pattern.
Have we run your budget up enough yet?
RE: Trophies can get really expensive. Decide what you want mounted, which a scull mount will do, and which just the crown is acceptable.
The skins get expensive too. If you just want pillows or something it is far cheaper to buy them there already sewn up, not the same but a quarter or less the price. I would also suggest having some veldshoes or vellies made if your in Windhoek. If your PH will direct you you can send in tracings of your feet and have them ready for pick up when you arrive there. I had a pair of Kudu skin ones that were comfortable from day one with no break in.