We use plastic 1 lb coffee cans mostly and freeze the fillets in a solid block like that. 3 lb marg containers work for a meal for 4 (when we have another couple over) The square ZipLock freezer containers are inexpensive and would be more space efficient and will use them if we ever need but we have a large freezer.

Our fillets keep forever, we have overlooked the occasional container and thawed out fish almost 2 yrs frozen with no noticable ill effects. I rinse & rinse & rinse my end product fillets then soak in the fridge for a day in saltwater w/fresh lemon or lime juice, then rinse again & pkg.

Deputy King, what kind of critter you astride of in your avitar? What does the farrier get in your neck of the woods for a trim (left barefoot)? A shoeing?
Just curious. $25 & $75 (I charge) and thats about average for here.