Immobilizer box problem Boxer 2,8 HDI

[LeonBoxer]

Hi,

I need a new yellow Delphi immobilzer box, The original one is not working at all.
There is no immobiliser light in the dashboard.
The light shall light up and then disappear if its working, and blink or stay lit if its something wrong.

I have a similar van, Fiat Ducato wich I borrowed the immo box from and then the immo light (code light ) appeared in the boxer (stayed lit)

My questions is:

Where can I get a new immo box from, coded to my van?
I have the electronic code for the car.

Thank you,

Sincerely Leon