Best wishes, Mark.
Sounds like a terrific endeavour, and a growth area if ever there was one.
For things I don’t grow on the Estate, I potter to my local http://www.lfm.org.uk/ – though my recent foray into chickens hasn’t gone as planned, as Gin & Tonic would have testified had they lasted. The Foxhunting ban has a lot to answer for!
Good luck with the shop!