Help with this gobelin?

Hi! Someone is offering me this French Gobelin; he says it's a Dubon brand from France and made during the second half of the XX century.
The frame is made of wood, gold leaf, and plaster. No glass. It measures 200 cm height, 90 cm tall.

My questions are:

Does anyone know more about this brand?
Do you all think that antique was made during the second half of the XX century?
How much does it value?

I am trying to get all this info before buying it to ensure I am making a good choice and not overpaying it.

Thanks!