Headers for RHD A body

Does anyone know if Lhd headers will fit Australian RHD ve valiant? the car has rack and pinion conversion so steering box clearance is no longer an issue.. problem is that noone here is aus has anything other than 1 5/8 primaries in a tri-y design and they are damn expensive! I would like at least 1 3/4 4into1 is possible...It's for a 500hp 408/727. any help is much appreciated
Cheers