Aussie 351C 2v's weighed in at a massive 719 pounds all up with flexplate, power steering bump and a/c compressor. (Ford Australia workshop manual). But the last ones were often thicker wall NASCAR block castings, and its not stated if this was the weight of this type.
According to Hot Rod, a ready to run 351C 4V weighes in at 582 pounds without power steering and air con. Alloy intake saves over 30 pounds on a 2V. The 351 Windsor HO 4V was 37 pounds lighter measured the same way.(Source was Wheels Magazine article on 351 Falcon GTHO'S in 1983)
The 5.0 Falcon V8, just a Mustang 5.0 EFI with extractors, was 198 pounds lighter than a factory 351C, at 527 pounds ready to run with power steering pump and air con. (Ford Australia press release at the return of the V8 Falcon in 1992.) Even though all alloy, the EFI unit is a bit of extra weight on the carby 302/5.0.
The Aussie cross flow alloy 3.3 or 4.1 in carby form is around 481 pounds, ready to run. No power steering pump. EFI versions were quoted as being 46 pounds heavier, but that was because of the electric fuel pump in the tank, not the engine itself. The alloy head saved 51 pounds on the cast iron variant. That's a heafty 532 pounds for 1976 to 1979 Aussie I6's, not suprising when it had a Cleveland style wide canted polyspherical head.
Then there is the Popular Mechanics article in 1972, which said the US 250 was 530 pounds ready to run.
Info I've seen on the little Ophan Annie 255 "Windsor" V8 was that it was 441 pounds. I just can't recall the source. This may have been without a/c but with power steering pump.
The US 200 and pre 1970 Aussie 200's are like pigmies compared to the 250 cube engines. 1.67 inches shorter, and that's a heap of windowed cast iron, rod and lighter crank that isn't swinging around!
My British Cortina's German Ford V6 runs in at 348 pounds as installed. Injected 2.8 V6's we had in German import Granada and Capri 2.8i were 358 pounds acroding to a British Motor magazine. For any person clever enough to throw an Aussie alloy head on a US 200 never designed to take the splayed pushrod head which fouls the block, my hat goes off to you. To weigh in at the same as a little 2.3 liter V6 is a treat with over 3.3 liters!