Rear diff noise

[Dyksy]

All,
I had a diff breather fail recently and ingested some sea water into my rear diff.
Didnt notice until the damage was done as in the whine started from the rear diff. I then flushed it twice with fresh oil and refilled it. The whine is significantly quieter.
I do have a renote trip planned in the future so i believe it will require replacement. Is the any tips tricks or thi gs to look out for when doing this? Also does anyone have any ideas of where to get a new diff or re furbed centre from please let me know.

Cheers

Dyksy