If you hunt in South Africa and take your own firearm (up to 5, one of which may be a handgun) your PH professional hunter will have to meet you at the airport (OR Tambo in Johannesburg). There is a police office and they will process your temp. import application (Form SAP 520, available on the internet). This could take an hour or longer. For a fee of about $70 -120 US a private firm can arrange all your South African permits for you. Search CHASA and PHASA. Your rifle and ammo will be released to you and your PH.
If you fly through the USA you also need an ATF permit, even if you never see your rifle after leaving Canada; could take 6-8 weeks.
If you hunt the Kalahari, some will use a 270, which I feel is too light. Go for a 30-06 with 150-165gr monometal bullets (Barnes -X or Hornady GMX), or 165-180gr premium bullets such as Nosler Partition or Swift A-Frame. In 300 Win Mag (not 300 WSM or any of the other 300 magnums, even though PMP in South Africa does load for the 300 H&H Mag) use 165-180gr monometal or 180-200gr premium bullets.
Going above 300 Win Mag, the only other calibre for which you will find ammo almost anywhere is the 375 H&H, although the 375 Ruger is gaining popularity, but few dealers will have ammo (Try VLT Arms in Pretoria = Ruger dealer.) Animals such as kudu gemsbuck, zebra and eland are big, tough and in the Kalahari distances could exceed 200-300m, so you want a powerfull flat shooting calibre with enough power at the target, but remember shot placement is the most important factor for a successful hunt.
Sako rifles are good, but expensive. I could not get my Sako 75 to work reliably when I had to do my PH qualification speed shoot in 2006, and eventually shot it with my Ruger 77 MK11. I have also owned 3 Tikka T3 rifles here in Canada (308 Win, 300 Win Mag, and 9,3x62 Mauser) and feel they offer more value for money than the expensive Sako rifles. At present I own several Ruger 77 Rifles (Hawkeye, Target and Safari Magnum) ranging in calibre from 22 LR to 458 Lott, and still believe these offer the best value for money in any serious and reliable rifle (dangerous game or tactical as in the Gunsite Scout).
At the end of the day a premium bullet, with good shot placement works best.
If you intend to take a handgun for hunting, only considder 44 Mag with 225gr monometal, or premium bullets as the 250gr Partition or 240 and 270 gr A-Frame. The 454 Casull is also very popular. A general 250gr hunting bullet will work well. The 460 S&W and 480 Ruger are also very poverful, but almost non existent as far as ammo in stores in South Africa are concerned. Go for a low magnification scope, 1 or 2 magnification, or a 1-4 variable. Ruger Super Redhawks with 7.5" barrels are about as long as hou could go. A shoulder holster works better than a holster on the hip, especially if you use a vehicle.
Also remember good shoes for the sand, and a hat and large water bottle!
Enjoy the hunt!