In 2000, a close acquaintance bought a 9x12 AND a 4x6 silk-on-wool for $3000. I don't know if that was some kind of superconcessional rate due to special circumstances or not, but he's pretty confident he didn't get fleeced.
This very person said that $1100 for a 6 x 9 sounds about average, but it really does depend on the knot count.
I am meeting with someone tomorrow who should be able to give me a better idea of pricing.