In Germany you have egun.de, gunfinder.de and vdb-waffen.de, in Austria there is waffengebraucht.at and in Italy there is armiusate.it.Calling @rookhawk and others. I have had several members ask what international gun sites do I use. My two favorite are Dorloc & Dorloc (spelling) in France where I bought my Westley Richards made 500 NE and UK Gun Trader.
I am sure there are many others