Thorn Cranks - who makes 'em

Ruston Weals
Ruston Weals Posts: 5
edited October 2009 in The workshop
Does anyone know who makes "Thorn Tandem Crankset for X-Over Drive - Front" cranks for SJS Cycles?
I have a 165mm right crank of this type and am trying to get a matching left crank. Although sold for tandem use the right crank I have looks like an ordinary 5 arm 110/74 triple. SJSC don't sell these crank arms separately so I thought I might be able to get it sold under another brand name. I have seen it said that Thorn cranks are re-badged Sugino XD cranks, but my crank is stamped XS2R. There doesn't seem to be a Sugino XS2.
Any ideas?