First you need to diagnose whats the problem with the engine, is it the injectors due to which you have starting problem or is it that engine has see its good days and now needs an overhaul...
If it is the injectors then new injectors for Vigo 1kd thai ones costed 120,000 and Chinese ones cost 80,000.... if its the engine then overhaul would cost atleast 2 lacs or more from toyota dealer.
If you want to swap the engine best engine to get is the 1kz-te which costs 2 lacs and they will adjust this engine in price...