Broken down - transfer box

Hi folks I have broken down. There was a noise from the tunnel area while driving which sounded like a loud rattle with a couple of quick loss of power for a split second and a nasty grinding noise as I slowed and pulled over.
Had to get it off a blind 60mph bend so there was more resistance as I had to limp off the road. Didn't sound good at all.
A friend has looked at her since and says I have a crack in the transfer box.
Obviously I'm trying to source a new box if anyone has one but I would like to know what other damage should I be looking for?
Regards Paul

Which version of Defender do you have, tdi, td5, tdci, or earlier?

It's a 110 with a 200tdi defender conversion.

I'd take the round PTO cover off and just check all looks well with the mainbox shaft.
Lt230 transfer boxes are plentiful and quite cheap especially disco ones.

We have had the inspection plate off and the bearing has collapsed. It's gone with that much force that it's split the transfer box.

Ouch!

Crikey!