At $950, without knowing what all they're doing and putting in them, it's hard to give you a straight answer.
If you're getting a good port job with quality valves* (Manley, Ferrea), new intake seats, bronze guides,
and machining for ACR. I'd say that's in the ball park and not a bad price.
(*I'd expect a 1.94/1.61 valve combination or similar)
Allot of people will put a 1.9 intake valve on the stock seat, but I don't recommend it. There are so many variables
and combinations, the price can vary greatly. You didn't mention the engine size, bike/rider weight or intended use.
So basically, it depends on what all you're wanting and how good the heads are. I'd say it's not a bad price if you're
getting all the good stuff put in them. If it's just a fluff-n-buff with small valves, not so much.
P.S: Nobody "polishes" ports anymore. That went out of style with hula-hoops and bell bottoms. lol