Back glass advise topic

The back glass of my Z3 is cracked, and sony refused to fix it for me under warranty !
So I looked onlinr for replacement part and found this
http://www.replacebase.co.uk/sony-xp...p#.VNVDiyw1NiN
Do you advise me to go ahead and bay it? Is it really original ?
The 12 months warranty is what making me think I should bay it
and is replacebase a good reliable site ?

thanks.