In the manual (on page 282 of Corolla) its mentioned that
For Diesel Engine: G-DLD-1, API CF-4, CF, 5W-30 and 10W-30
So if the engine is healthy, then the ideal choice would Toyota's Tin Pack oil for Diesel. Its CF and viscosity is 10w-30.
It comes in 4L & 6L packing. 2C engine takes 5.1L alongwith filter cap. So you may try to find this oil in 6L packing. Change interval 4K.
Second choice, ZIC 5000. This oil is 10w-40 and meets CI-4 which is latest for diesel engines and is more towards fuel efficiency. Its change interval as 4000km is fine. Some people go for 5~6K on this oil.
Third Choice, Delo Gold (15W-40).