HP Pump

My 2005 TD4 has started to leak diesel from the top cover of the injector pump. Trying to save a bit of money/time I ordered a part from an online breakers. The replacement was meant to come off a 2006 low mileage Freelander.
Well this turned up today (see picture) dont look like what I was expecting - have just phoned them and they reckon there nothing wrong with it and it came off a running car. Refusing to pay my money back, and only offering an exchange

You could get in touch with Bosch (email) quoting the serial number and ask date of manufacture, have you confirmation of the 2006 date or was it verbal ?
if it was verbal and they won't back down then the only options you've got is to go for a replacement or fit it and hope for the best (if it turns out to be faulty they will still have to replace it)