Great price, indeed.
And yes, made in the same factory as the similar Tama TC 8/10/15 and Juan Orozco Model 8/10/15 (but not original Kohno or Sakurai), and just labeled differently.
Very close in sound to Masaru Kohno guitars, so you got yourself and excellent guitar for a steal of a price.
I own a Juan Orozco Model 10 (the Ibanez equivalent would be GS-10).
GS-8 and GS-10 must be similar. Both are built with Indian Rosewood B&S and should have the two ebony reinforcement stripes on the back of the neck.
The model numbers most likely reflected the price, just like for Kohno, Sakurai and other Japanese instruments.
But my impression based on owning both Orozco and Kohno guitars is that the Ibanez/Tama/Orozco were equivalent in construction with the next higher Kohno model. So your guitar would be equivalent with a Masaru Kohno #10.
The price of your GS-8 was definitely higher than $280, most likely $800 - $1000.
A few years ago there used to be more info about these instruments on the Web, but not much so anymore.
You may check these:
(see the info about TC 8 to 15 models at the bottom of that list, including prices)
There is also some more info on this forum. See for example:
www.classicalguitardelcamp.com/viewtopi ... 7&t=122336
May I ask you to post some pictures when you receive the guitar?