The procedure you followed, i.e. ordering your bricks via a builder's merchant is standard practice as brick manufacturer's will not sell direct, no matter how big the quantity. As suggested by Lorz your best bet is to track down the rep. from Country Manor Bricks, explain the situation and ask them to dig you out, given that you acted on his advice, indeed I would invite him to view the bricks delivered. By any chance did he give you a sample of the brick before you ordered (which could be compared against the bricks delivered)? The quantity of bricks ordered is small beer to HB or CMB and CMB should be able to organise a credit note for you and arrange for their return at no cost to you. Failing all that you may have to suffer the loss (about €450?), but you may be able to find a buyer through Buy and Sell. Could you use them in landscaping/ paving of your garden? For what it's worth Ibstock do a great brick.