I did find this Lee Enfield no. 4 at Shoot and Scoot. They also have a kit if you want to go that rout. I dont know much about the company or if they are reliable. I have never ordered there. I am waiting for them to come out with their resin moulded G43 reciever so I can finish my project. Supposed to have it out soon. They seem to have alot of British gear as well.
http://www.shootandscoot.co.uk/shop/lee-enfield-no-4/