differential carrier issue + used parts case

Dear Colleagues;

Please let me know if anyone have ever encountered below issue with installing Axle Shaft into differential carrier?

Due to Left Driveshaft damage (splines on the driveshaft between inboard side end and groove damaged) I bought new driveshaft [http://ift.tt/2p0lGxI] but failed to install it to the gearbox. I faced the obstruction inside the differential carrier (LSD ?) to put the shaft into right position. Whenever I try, the set ring is not going to lock in the groove.
Does it automatically mean the differential carrier is to be replaced?


Second case is: I am happy owner of 06 RSX Type-S K20Z1 from Poland, Europe. I shipped it from US Dec 2016. All is fine but as Acura is not present in European market - I face constant issues with spare parts (honestly -as expected) - do you know any repository that will tell me if I can use parts from other Honda models as a replacement?
For example: if above issue resolves differential carrier to be replaced - can I check somehow if I can use Integra or Civic differential carrier from European models?

Thanks a lot!
Konrad

differential carrier issue + used parts case