don't know about hambledon but some great ones around swanmore/corhampton...trying to remember the name but there's a lovely one right out the back of mayhill stud in droxford, 'swanmore park' maybe? some xc, nice school, gallops, post and rail. is that too far?
often the real livery gems aren't advertised everywhere cos they do fine through word of mouth. so maybe just take a drive around and have a nose? it's not a very big area. good luck!
It's been a while since I have been up there, but pretty sure both Rushmere Stud and Rushmere Farm on Speltham Hill both have post and rail, and are both very well run.
I know someone who is very happy with a yard on the Worlds End Road - possibly Bittles Farm, although I think this is electric fencing.
Or you could try Hill House at the top of Bunns Lane