Ah, sorry didn't see your 1st paragraph :)
Yup, yung LD would be a good choice for the vanette. Pero AFAIK, it's very hard to come by dito satin sa Pinas. It's an old engine from the datsun era pa. Even if you find one, baka mahirapan ka sa parts.
Ang isang napaka ganda sa mga rear wheel drive na oto is pwede ka magswap in nang kahit anong rear wheel drive na makina na kahit ibang brand as long as kasya sa engine bay. Dalawa or tatlo lang kadalasan ang mga pyesa na kino-customize. Motor mounts, drive shaft, and sometimes yung oil pan.
Try checking out other brand diesel engines na kasya sa engine bay ng vanette na readily available dito satin sa pinas bro. It'll be more practical, IMO.
HTH