or you could post an ad on advrider.com
advrider has TONS of travel bikes and you can find a sell that has a lot of posts for added security. You can see what posts the profile has written and if he has several hundred then he is probably a regular and would not cheat you.
another option is to ask someone to buy a bike for you. I did that and a guy from advrider bought it for me a did all the registration so that I could arrive and drive off. You should probably pay the guy a bit for his time though, but I found this a very good way to do it.
South East Asia, USA, Central and South America and Scandinavia.