Dodge phoenix arms  will probably be generic C body arms
i wasn't aware of any RHD or LHD handed-ness  in the actual arm pressing.  
(obviously there is a Left hand side and right hand side arm)
i.e i thought they were just mirror image of each other and the orgin of the car made no odds
I thought i could use US A body arms on my car with no probs 
i thought any slight tweaks  for road camber in left and right hand drive situations   were part of adjustment or a function of the mountintg on the chassis.
the guys in Oz are happy to use  tubular arms from the US on their RHD cars.
you have way more experience with this than i do i.e seen many more cars so i'm  baseing this on just mine 
as far as i can tell it matters not  which side the steering wheel is on
the arms are stamped  to  put the top balljoint  directly above or just ahead of the bottom joint  to give neutral or negative castor  (which was the fasion in them there days) 
so  to get some positive caster  you needed the front pivot mount of the arm  further out from the center  of the car than the back pivot to pull the top balljoint back in relation to the bottom  so a line through the centre of each balljoint ball hit the road  just infront of the centre of the contact patch of the tyre.
i.e you lengthen the side of the triangular arm at the front and shorten it at the rear  to sweep the upper balljoint back towards the A post
and there was just never enough  movement on both bolts to do that
you needed much bigger offset washers and a longer slot at the mount
i.e  front bolt with fat side of washer in towards chassis rail moves front pivot out
back bolt with fat side of washer directly pointing out moves rear pivot in
and the top balljoint moves back a smidge 
back bolt then sits closer to chasis rail than front bolt and you should approach  neutral or some positive castor provided you car does NOT have a rake  i.e nose down attitude to start with.
offset bushes  
put them in to exacerbate the situation further
so if you have your bolt on the front set, out-wide  to move the front side of the arm out further  you need the thin bit of the bush inner most so the arm sits even further out.   you run the innner section of the ARM eye  as close to the already spaced out bolt as posible
You alter the pivot point from the centre of the hole in the arm  to car side of it  effectivly lengthening the front side of the tringular arm 
and then do the reverse at the back bolt  fat side of bush inwards making the outer edge of the arm eye closer to the already wound in bolt efectivly shortening the rear side of the tringular arm
I believe, but cannot confirm until i find the right magasine that this goes againts the instructions that come with the bushes
they are offset and have arrows on them designed to achive  more negative castor.
negative castor  being what was  dictated by chrsyler  at the time the car was made  to give floaty light power steering so that you could steer that 3 tonne car even if you were 96 and had arm made of string and feathers for fingers
now all of my assumptions could well be wrong  and i have in the past got me offset bushes arse about elbow, this time i drew a picture and it seems right.
 
on the other hand
 if RHD arms are special 
some off a phoenix might work... didn't C bodies have different upper bushes??
however i bet the mounts  are welded to the car so impresciely that any difference in the arms  is spoilt by poor QA when welding the body together..... or previous kerbing
you might get them off
TJ wreckers  in dandenog
http://www.google.co.uk/#sclient=psy-ab ... 66&bih=572
the valiant guy
http://www.thevaliantguy.com.au/
queensland valiant spares
http://valiantspares.com.au/
 
Dave