M1 garand
enjoy the thumb, also these are a bit expensive
mosin (nagant)
I have one and its $180 for good reason. Cheap, inaccurate surplus rifle. Can't even make a 5" group 50m away
gewehr
I hear these are so stufftily made but the accuracy is decent. I've read a lot of times that the gas system is so harsh that it cracks the receiver.
Not sure about Belgium gun laws, but if you want something reliable, lightweight, cheap, accurate and all around a VERY decent rifle I would definitely recommend a Czech VZ58. I have one made by Century Arms and the ONLY complaint I have with it is that the handguard gets very hot after a magazine.
Nothing some gloves or in my case, new polymer furniture, can't fix.

I cannot stress how great this rifle is and if you can own one in Belgiumese than you should def consider. I've shot 500+ rounds through it with not a single malfunction, and using a wide spread of ammo. Even reloads.
I can hit a gong from 100m with the
iron sights. I haven't mounted any optic on it and I don't plan to, but if you wanted to you could.

Mine looks like this but instead has tan furniture instead of the black one this has.