Quick update. I phoned the parts supplier in question this morning and queried this. I just said that, given the amount of money spent, i was concerned that a pattern part had been sent to me by mistake. They explained that sometimes the parts have no manufacturers stamp on them - even genuine depending on who LR gets to make them.
They said that if the box looked untampered, and had a genuine LR sticker on it, it definately will be genuine. However as previously mentioned, its easy for boxes to be 'recycled'.
The bottom line is i have no way to disprove them.
Im not naming the parts supplier as they have been good in the past but if i find ive been sent pattern goods for genuine money i certainly will!