I have the graphs if you would like them Sam - PM me.
The shortest Tarmac runway I've been in and out of is 500m with low fuel and 2pob. The PA32 can be a ground hog! With the wind blowing down the runway and a nice cold day etc you might do a little better but who can guarantee those ideal conditions?!
I use Elmsett a few times a year 900m grass. The grass is perfect there, well maintained, rolled and mowed short like a bowling green. Landing is never a problem (there is an upslope on one runway) I can get down in half the distance easily If the approach speed is nice and stable. Takeoff I wouldn't want to push it in light wind and higer temps with fuller fuel and more POB it always feels tight!