12″ rough is “normal” from the finished wall. BUT in case of a screw up you can go as small as 10 ” or as far away as 14″
Your best bet is to pick out the toilet you like and ask for the ruffing measurements.
Some colors only come in the 12″ and then you have to resort to offset closet flanges which in some localities are illegal.
You also can look at “Flushometer” type of toilets with either a top spud or back spud which are common in one family homes around here.
Again best bet look at the ruffing on the model you like. Hey have a great week end