Get your manual and post what the specs are for that exact transformer (at a rough guess, forgetting part numbers, it shld be no different to a current Stern I would think cause Stern/Sega made the x files one) ??
by posting the transformers exact specs from the Sega manual, people can perhaps search for a transformer with the correct specs versus a part number which may not exist anywhere anymore. Also, post a photo of what yours looks like with a close up of the stickers on the transformer if u can giving the specs..
Also, I reckon XXXX would have one in stock perhaps 2nd hand cause he has wrecked a x files and a few jurrasic park lost world segas - all concave headbox models - persons details sent just in case he can help
hope it helps
Brett