I have not seen a Belgian "Parker" knock-off with a 'PF' mark
The maker could have been Pirlot & Frésart
http://www.littlegun.be/arme%20belge...esart%20gb.htm
or Pirlot Frères
http://www.littlegun.be/arme%20belge...reres%20gb.htm
It is a lower quality gun with Twist barrels and does not carry smokeless powder proof. You might squirt some epoxy in the firing pin holes before hanging it up to protect the unknowing from themselves.