2.0HDi gearbox type?

[Emil Solberg]

I've recently bought a Partner 2.0 HDi, but the gearbox went 'kaboom' yesterday.... ? 
The geabox id says: 20DM79, does anyone know of any other gearboxes that might be interchangeabl? 20DL80 maybe?

Any help will be greatly appreciated! ?

Cheers!