Looking for a dog - advice on how to choose 'the one'

[ididntsignupforthis1]

We have a lurcher bitch(saluki greyhound) about 12 years old.
She is slowing down and often won't walk (get out of the car, sniff, poo and then sit next to the boot)
Or if we start on the lead then when we let her off she might - depending on how she's feeling - just turn round and walk back the way we've come.
She's gentle, lives for strokes , gets on with all people and dogs, cats, doesn't pay attention to birds and sheep, has recall.
We are thinking of getting another rescue. We want a dog that will get on with her and will like walking, preferably be able to go off the lead. We like the saluki in her. We have seen a couple of 18month - 2 year olds (saluki grey) and been told about a litter of 8 week old saluki Bedlington boys. (all via rescue centre)
Ideas how to choose?
If it's a pup how do you pick the suitable temperament? We want not dominant, more gentle type dog.
Can you all give us tips?

I'd phone a rescue who specialise in sighthounds and explain about your current dog and ask if they have anyone who sounds like they'd get on with her. Then go and meet them with her so you can see what she thinks.
I'd say at 12 a puppy might be too much for her to put up with - though obv you can't tell.

Pip at EGLR is fab, and they have some lovely dogs in foster atm. Both of mine came from them - ddog1 is prob a salukixgrey and is wonderful

I would say avoid a puppy too. We have a 4.5year old bitch and puppy. Older girl is still quite playful and v active but the puppy does her head in at times (how i wish she would tell her to naff off but she doesn't). Constantly biting her feet, trying to bounce on her, chewing her collar and holding onto it. just generally a royal PITA.