Just like Xulfiqar bhai said. Keep the old engine. Your resale wont be damaged then.
There are people who will gladly pay more for the bigger engine too.
Swap a 1.3 Carby. Would cost less. The swap labour cost of an EFi engine goes easily to 20k with all the wiring. Also you need to make sure that price your given includes ECU + all sensors + wiring. There is usually one or two missing all the time. Kabar market walay ... pfft.