You should talk to a customs agent, you will need one, everything imported goes through one.
They are go-betweens representing you, not the actual agents at the Customs dept.
Some are unscrupulous, will conspire to extort you in collusion with actual Customs dept.
Guns and ammo are a hot issue here.
There are restrictions on caliber (9 MM or smaller) and no ammo common elsewhere, like 12 gauge, 16's are common here.
I had great luck with Victor Murillo, but I didn't import any firearms.