Joseph Fiennes database address?

[BeckyDuck]

Hello, my name is Becky and this is my first time sending anything to anyone so I want to do it right. I would love to get an autograph from Joseph Fiennes and found an address on this site but on the feeback section most of the feedbacks said they used a different adress (unless I've confused it?). I was wondering if anyone had sucess using the one from Ken McReddie Associates?
I am living in America but was thinking to save on postage I could give my sister the envelope, pictures and stamps and have her send it from her new home in Italy then just bring it home with her bags when she comes for Holiday. Would this work or would it make it harder because of Italy's postage process?
Also I have no idea what an SAE is, could someone explain this to me?

Sorry for so many questions but I am new and have never done this before! Thank you in advance!