If your local dealer puts the part on the critical list with a customer waiting it usually only takes a week to come from Japan, have you actually tried to order one? If it says it's on "back order" that doesn't necessarily mean it will take months. I'll be surprised if there isn't one in stock in the european warehouse.
2001 HONDA INSIGHT DX FRONT LOWER ARM - Original Honda Parts | Lings Honda | Honda Cars
There was red one on e-bay months ago in a breakers yard someone will remember where or you could search on here for details they have been posted before.
The red one is the only one we are aware of in a scrap yard in UK
AFAIK there was a blue one in scotland but that went to the crusher I believe.
I only have a passenger side one spare sorry.
I can't remember if anyone from the UK owners got the right hand side one from the car we broke last summer. They may chip in on this thread.