1.4 TDCI and 1.6 TDCI Fiestas can be had for more or less the same price on Pistionheads.
http://pistonheads.co.uk/sales/2045980.htm
http://pistonheads.co.uk/sales/1976543.htm
Pretty sure he's talking about the MK7 (? newest one?) seeing as he's concerned about warranty.