The rescues are full of kittens at the moment. We had 6 mothers and kittens dumped on us yesterday and I'm just about to go out and pick up another one who broke into someone's house yesterday to give birth in their understairs cupboard. So if you want kittens there are thousands. And there are plenty of shorthaired ones. Do orientals have shorter hair than normal shorthaired moggies? If your children are very young though then small kittens wouldn't be suitable - whether pedigree or not. However if they're sensible and can be trusted with kittens then it should be fine.
If you buy a kitten you are encouraging people to bring yet more cats into a world where there are already too many. So you are being part of the problem, whereas if you were to offer your home to rescues you could be part of the solution.
We come across appalling cruelty caused by breeders and have just in fact won a court case against one. Breeders can do a lot to make it look as though they treat their cats well while keeping the reality well hidden.
Why not consider fostering a mum and kittens? (You would need to have a spare room if you want to do this, or at least a room where your children don't go). That way you could get to know them, and see how the allergy situation is, and if they don't fit in, you can give them back, but if it works out then you can keep a couple.