Upgrading and engine with that amount of mileage will cause problems, more stress to everything, and clutch will likely be toast within a week of turboing it. Not to mention the cost and the fact the Endura-E engine isn't suited for tuning. It derives from a 1950's Ford Anglia.

Buy a Ford Puma from the exact same reg and swap the whole wiring harness over and it's plug and play. I wouldn't just buy the 1.7 Puma engine on its own. A 1.7L Puma engined Fiesta will smoke an endura 1.3L turbo with less than half the cost of spending to turbo the endura e.