I think that's an XL185/200 stator. The XL's had three coils like that, one was a charging coil for the battery, one was a lighting coil for the headlight and high beam indicator only, and the third was the typical source coil for the cdi. I have one around somewhere, but I just looked, and can't find it at the moment to compare to your pics. Try going on Partzilla, I think you'll see that the XL's all had three coils instead of the two you'd find on an XR or a 200X. Hope this helps!
1985 Tri-Z 250
1985 ATC250R