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It does seem that way.
If this was me choosing that particular reward I'd be inclined to check with Customer service on 191 or Live Chat.
If you go down the line of placing an order, you should get some further details before you confirm that you want to go ahead.
I've ordered earphones and a micro-USB cable in the past, and the details have included something along the lines of "colours may vary, if the product is not available you may be provided with an alternative of similar value."
In both cases, I did get what I had ordered, but not in the colour illustrated. I'd certainly think that you'd get the next design out of the box, on the basis of what I can see in the catalogue once I've logged in.