I normally eat canned tuna, I have been getting into salmon lately though for some variety. The John West Tempters are the best in my opinion so I am loading up now when they are half price.
I do recommend getting the olive all variety over springwater as it is over double the calories for the same price. The oil works as a nice salad dressing too, I usually pair it with diced carrot and shredded lettuce.
https://www.woolworths.com.au/shop/productdetails/346124