Hey, Targan,
thanks for your thoughts.
My actual campaign is set in Poland. And I think you are defenitely right. The slavers, I have in mind, would not be in some official service. I think about a "unit" of independend slavers/slave traders, who's patron is a local strongman. This patron should be "bad", so he's not a person, who has any legal right to slave or imprison persons.
And that's the reason, why I think about the whole organisation or infrastructure of such a group. The slavers will be aware, that they will get in deep trouble, if they encounter any military or militia unit. Therefore they will avoid major roads and will have to scout their way through the "bushland". Such a transport will certainly be more difficult, for slavers and their victims alike!
They will obviously try to avoid encounters with anybody.
I was a little disapointed: Paul has no prices for slaves on his page
