I think the breeder is following standard guidelines set out by the cat fancy, regarding her pricing. Most pedigree cats, regardless of breed are sold at a similar price bracket - unlike dogs where the breeder sets the price according to whatever they think they can get.
Not sure why there is a difference in price though, perhaps the breeder has found that more people prefer girls. I think the cat fancy also recommends kittens are sold fully vaccinated which would make them 12 weeks. Many breeders will not release pedigree papers until they have a vet letter stating the cat has been neutered, it probably depends on vet preference whether they are kept and neutered young, if the local vet is happy to do it then it's not such a stretch for the breeder to keep hold of them and just sell them neutered.
Of course, the price of the kitten would include the price of innoculations and spaying (oh that will be why there is a difference in price - it's cheaper to castrate a boy than spay a girl).
I don't have a problem with what the breeder has done here, we all see how many dogs/cats end up in rescue centres and how many are sold as something they are not. I also see pedigree breeders (mostly dog) that keep there animals in dreadful conditions and sell puppies full of fleas and worms.
So I don't think the price is excessive or that making sure his/her animals are not going to be bred inappropriately is a problem. I'd be more wary of a 'pedigree'
cat breeder that was selling young and cheap kittens to be honest.
>gets off high horse now...