here's a picture of the real braclet from the tiffany's site :
while they do look alike, i would just get the real one. you said you could get it on ebay for $90 - plus shipping and handeling, maybe insurance. thats almost $100 - the one from the store, brand new is $135 - not that much more. plus you know its real and it comes in that fabulous blue box
otherwise, there are some good fake ones for cheap if you don't want to spend a lot.