Hi there,
I can personally vouch for lineafashion.com as I have shopped there for over 15 years! They actually have a 'bricks and mortar' shop in London, Hampstead which was established in 1991. I think they have been online since about 2003.
The owners names are Moreno and Piero and they work in the shop - I consider Piero my personal fashion guru!
I guarantee you have no worries purchasing from them; their service is impeccable and everything they sell is 100% authentic - it would have to be for them to have been established for so long.
If you have any other questions message me!
Oh yeah, here's a link to their site which has a picture of their shop: