I'm just purely guessing here, rattlewatch, but I think there are approximately a minimum of 50 BCT's. Now, I also think there are different types (troop, artillery, etc.) of BCT's, so maybe that number is closer to 100. Just my wild guess.
As far as cost, (and i'm not sure, don't remember, where I got this exactly, in the the memory bank), but i'm thinking that a BiB 250 has a cost of approximately $250K, a 100 has an approx. $100K cost, and so on. I'm making it sound easy, the model number matches the cost.
Again, i'm just purely wild-guessing about all of that.
I don't have a guess for how much a WASP might cost.