It seems strange that you say that the jap lights won't fit the aussie/uk micra because I have nismo side indicators in my car and a guy I know who works in nissan spare parts had them in his too. I found the only issue to be that the globe holder from the aussie/uk car does not bayonet into the nismo light, different number of locating lugs, one has 2 the other has 3.
Thats how it is though. I've seen them myself and the Jap quarter panels have a smaller cutout for the indicator body. Clearly this means the jap indicators have a smaller body (same overall lense size as the aus/UK though).
I've seen quite a few aus/UK made k11 running around with the jap indicators and headlights though. Plus there's a few getting around here with the jap tailgate.
If your cars have ever been in a smash before the panels were probably replaced with jap parts. No biggie, just means you can get higher quality side indicators
Car definately has original aussie/uk panels, I have trial fitted these nismo indicators into the other 2 micras that I have and they fit just fine. All 3 of these cars have original panels
Definately nismo, genuine packaging and part numbers from nismo catalogue, bought through nissan dealer, and as I said one of the spare parts guys at this particular nissan dealer had them in his aussie super s too.