2000.
I agree with this answer; but after uncountable viewings of this movie, and hearing Luke's disappointment with how much he got for his speeder, I wonder if he received the 2000 they were hoping for. Ben then says, "It'll be enough." So maybe they were able to come up with 1950 or something, and Ben figured Han would be satisfied with that. Or maybe I've just watched this movie too much and I am over analyzing it.