Sorry mate i aint got a clue, Not many here in ireland for breaking, i'm lookin for a few bits and bobs myself, but nothin yet, One of the other lads that will know more will be along before the day is out with some better advice for ya,
Have you looked on NASOC(North american subaru owners club), I'm sure you mite find out from one of them lads if there are any b4's with HID lights they'd know,
Also there is a conversion kit you can buy, I dont know the site but i definately read up on it before, As i said one of the other lads on here may be more help than myself, Hope you get sorted. Keep us updated.
John