I believe the above is correct. The TRB 100x are indeed not MIJ but probably in <enter far eastern country here>. That said, i've played a few TRB100x series and they've been great. The main difference I suppose is body wood, the TRB5II will be ash, the TRB1005 will be alder with flamed maple top I believe.
If you can afford it then go for the TRB5II, if you can't then don't worry about it - you're still getting a fantastically good bass.