I am not into these animals, but the number of species offered, seems to be very limited. Mastigoproctus giganteus (from US) and some Thelyphonus spec from Asia are sometimes offered.
these animals are difficult to breed, young are hard to take care for. So, I would go for adult specimens if I where you. I hope you can find more information.
You can take a look at the non-venomous animals section, in the Uropygi (= whip scorpions) section of the website The Venomlist. There is a caresheet on M.giganteus ("giant vinegaroon") there or you could simply use the search function of Arachnoboards.