I'm living and working in Senegal and am looking for a bike that would allow me to do some long-distance touring in the next couple of years. Specifically, I'd like to travel around West Africa in the near future and then eventually also take the road up to Morocco in to Europe and on East.

I'm on a tight budget ($1500 max) and have limited options so I'm willing to make compromises, but optimally I'd like something that can handle some of the tough roads while also giving me decent travel times on the pavement for longer distances.

Up till now I've been driving around a borrowed Chinese-model 150cc, which comes in various models and make up about 75% of the traffic down where I am. One option is to get a new one of these (roughly 700 dollars + another 300 for papers), but I'm reluctant because all of the ones down here are in terrible shape and seem to break down all the time. Definitely a consequence of lack of maintenance and constant use, but I still wonder if with better care it could last for 2 years without lots of issues. On the plus side, tons of parts are available and everyone in the region knows how to fix them.

Other option is to buy a pre-owned bike from someone in the expat community. These are real brand names and have papers but are mostly out of my price range. Also, all depends what people post in classifieds (listing here -> Expat Dakar - Le site incontournable des expatriés de Dakar) so a limited range of choices.

Ideas? Go with a cheap chinese and keep it maintained? Keep a look-out for a specific used bike in classifieds? Any info or recommendations appreciated.
Thanks,
Jeff