Theres a guy on ebay advertising conversions to the 2.8 engine, lots of those about with no gearbox.
If you really stuck and can find a 1.9 from a tempra 93-96 should bolt in but the torque curve mightn't be ideal for the van, your cam may swap in though.
Ebay ad text is below:
WE CAN REPLACE YOUR SLOW, TIRED 2.5 DIESEL ENGINE USING EITHER THE 2ND GENERATION 2.8 FIAT ENGINE OR EVEN THE 3RD GENERATION 103 HP IVECO UNIT.
*NO NEED FOR GEARBOX CHANGES, WE USE YOUR EXISTING UNIT
*BIG DIFFERENCE IN POWER+TORQUE
*BETTER ECONOMY!
*NO MORE TRAFFIC QUEUES BEHIND YOU!
*ALL PROFFESIONALLY DONE WITH EITHER RECONDITIONED OR WARRANTIED SECOND HAND UNITS
*ALL WORK FULLY GUARANTEED
P.O.A.
RING MOTEK DERBY LTD FOR DETAILS ASK FOR MARTYN OR ANTHONY
CONTACT NO 01332 525327
07790062980