What do you mean by renting? Are you thinking about getting a checkout and then flying around as PIC on an FAA license? There are some outfits using N-registered planes- like MAF in Mozambique and ASI until they pulled out a year ago. However I dont know of any who offer their planes for rent. Problems with FAA approved maintenance/ FAA qualified A&Ps, on and on. If non "local" registered planes are allowed to operate commercially a country registration with a "loose" regulatory environment is preferred.
As of a year ago CC Pocock in Barberton RSA gave bush pilot courses but not in N- registered planes.
probably easier to just get a validation to fly the local registered a/c. Many outfits in RSA provide this service.