Cheapest engine for 2005 ford Transit Connect Diesel Van

Ford
Model 1-02-06 1800cc Engine Code: BHPA TDdi 4 CYLINDER INLINE 16 VALVE
Engine Code: BHPA Next Step
Ford
Model 2- 02-06 1800cc Engine Code:HCPA TDCI 4 CYLINDER INLINE 16 VALVE
Engine Code: HCPA Next Step
Ford
Model 3- 02-06 1800cc Engine Code:HCPB TDCI 4 CYLINDER INLINE 8 VALVE
Engine Code: HCPB Next Step