VIMAN,
There are two sources of Fresh fish near Sosua. One is the guy that stands on the corner of La Mulata Rd and the Main Highway from agbout 9 am most mornings. He has fish caught that morning and it is what every he caught. They are gutted but not as far as I can see descaled.
The other source in the fishermans port under El Tablon , in Charamicos. They fish there early in the morning and it is possible to get filletted fish there about 10 or 11 am. To find it is difficult. You go into Charamicos , first right before the traffic lights towards the School and Bandstand. Go straight across the junction and follow the road round - it is a one way system , You will come to a y fork , turn Right again until you get to a road going left with a green painted colmado on the corner, go up that road, and you will get to a three was split,to the right, take the middle rough road that leads down the hill. Follow for about 1.5 Km and at the beach go to you left and the pescadoria is there. You will see the boats pulled up any way. And you are there.
Hope that helps.
Olly and the Team