I had a a few minutes free to assuage my curiosity and yes indeed it was Gabon, but the airline Gabon Express ceased operating in 2004, so said Caravelle is most likely sitting in Libreville gathering dust. Here's a little video about the airline that features the HS748 and the Caravelle, simply filmed, but charming.
That particular Caravelle (3D-SEP) sat idle at Rand airport in South Africa after Gabon Express ran into trouble in Gabon. It was added to the Waltair fleet, run by Jacques "Kiki" Lemaire and registered 3D-KIK. It crashed and burned August 28th, 2004 when executing a landing at Gisenyi Airport (Rwanda). The Caravelle was originally destined to land at Goma, DRC but was refused landing an diverted to Gisenyi. Transair has also been mentioned as a possible operator.