No, it's definitely a Ford Windsor block. Look at the shape of the pan rails, the location of the freeze plugs and oil filter adapter and the position of the motor mount lugs. The heads, crank, balancer, timing cover and flex plate are also Windsor parts. I'd say it's '79 or newer because it appears to have the dipstick tube hole in the pan rail (look just above the lower left freeze plug in Teg's picture and compare it to the early block in the picture below).
The only way to know for sure if it's a 351 or a 302 would be to either check casting numbers, or the quick way for a late block is to measure the head bolt holes... 7/16" = 302, 1/2" = 351.
The water pump is from a 3.8 liter GM engine found in zillions of FWD cars and would be useful only to sell as scrap aluminum.