A lot of people I know have cats and Salukis. Providing you are clear headed about the risks and manage accordingly you will be fine.
Do your cats run from a confrontation? That is usually what will trigger prey drive in a sighthound, if it's not moving, they are rarely interested. If the cat holds its ground, particularly if the cat biffs the dog on the nose as a puppy, the dog will generally learn a healthy respect. It's easier to manage if the dog is a single dog too, less chance of the dogs forming a pack.
All our cats have died of old age, however we never allowed them to be unsupervised with the dogs and they always had places they could go to escape the dogs. There were also house rules against running and chasing. Given the right set of circumstances, any sighthound (any dog really) is capable of killing a cat. One of the reasons we didn't get another cat when our last cat died was because we have 5 indoor dogs and they're all very drivey. It's not so much that they "turn" it's that they have been bred for thousands of years to chase small running things, and training against that is hard for even experienced people.
The chickens are a problem. You won't be able to have a visiting Saluki offlead with your parents chickens but you won't be able to have many dogs offlead with strange chickens. If there are areas on the property where the chooks don't go, you should be fine tho'.
If you talk to a breeder about your circumstances, they can pick a puppy that isn't very drivey for you.
The one cat doesn't run and doesn't exhibit much inhibition when it comes to overfriendly dogginess. The other is very nervy and cat-like, and yes runs.
The thing I worry about is if ever my parents babysit the dog and get a little sloppy with the 'rules' I've used to safeguard. eg. no off-leash walking, supervision with small animals, etc.
What I could do until I'm absolutely certain the dog is fairly well trained is muzzle it when with my parents and just ask them to keep it ON. I know it's a bit excessive, but better to be safe.
Re: keeping the animals separate, it's a little bit difficult because cats and dogs will both be indoor. Do I give the dog the reign of the downstairs and the cat upstairs sort of thing?
Chickens are suburban free range (Bellevue Hill would you believe!) But I'm happy to do contribute to the design and cost of a chicken enclosure. The remaining problem would be the one skittish cat. The other dogs, cockers don't really concern themselves with anything but food.
Would you suggest a retired Grey or a puppy Saluki to be cat-safe?