where to purchase sim free Apple iPhone 6s 64gb

[MindfulBear]

I am looking at replacing my iPhone 4 with an iPhone 6s - new, refurbished or used..... But not on a contract so I have the flexibility to replace it when I want to.
I'm on PAYG at the moment and barely spend anything so buying sim free iphone suits me!

Can anyone recommend a good deal please? Preferably iPhone 6s 64gb rose gold......