Hello and Merry Christmas.
Mossberg did make several firearms for retailers. Some were labeled as Western Field (Mont. Ward), Revelation (Western Auto) and probably several others for local/regional retailers.
If I recall correctly, the 712 in question may be a derivative of the Savage 340 series. This was a fine little bolt action that required a side mount for the scope due to not having an enclosed receiver. I believe the .30-30 version is more popular.
I've seen one 340 in .222 and it was a very nice example. It had a much fancier stock than the typical 340 and what appeared to be a longer than usual barrel. The finish was a nice deep blue, as well.
You may want to make an inquiry over at the Savage forum for more info. There has been some discussion on the 340 series from time to time.
EDIT: After writing this response, I moved to the Savage forum and saw that there is a current topic regarding the Savage 340 series in .222. Another member confirms the 712 as a version of the 340.