Hello Drew – nice bike. I wouldn’t worry about the rear hub if I was you. If your bike is a 1929 tourer (which I think it is) the rear hub should be a Webb hub rather than an Enfield cush hub – yours looks right to me but I’m prepared to be put right if I’m not!!
I will try to copy and post the picture from the 1929 brochure which will show that your bike is pretty much correct, subject to a few touches such as the exhaust.
Send a request to John Underhill, the club registrar and he will probably have details of your bike and the works records are with the VMCC in Burton on Trent which will give you conclusive details of its dispatch. (However, I think 1928-9 records might be missing).
Welcome to the club!