Halter for a Greyhound

I know greyhounds don't traditionally wear a halter type collar and I'm not sure Snowy would take to one, but I want to try. We are taking her more and more places with us. She wears a 1" wide nylon adjustable collar now. Since greyhounds heads are a tad bit smaller than their necks, if she backs off from the leash, she can pull right out of the collar. This worries me and I want to try something safer. We will be taking her and Baby to the TNRU in May.

Any experience on this and/or where to get a halter to fit preferably the same type of nylon staps. Help is appreciated.

Thanks,
Molly