Update
Thankyou all for the lovely comments, I wish everyone shared our attitudes towards our companion animals. Unfortunately, there are various degrees of cruelty and neglect happening everywhere in our communities and not all have happy endings like this little guy. I was in the fortunate position to be able to offer him a stay in my home to recuperate and its been lots of fun having him here.
I took this photo yesterday (at three and a half weeks) trying to get a similar angle to the newspaper photo for comparison. Puppy weighed in at 12.1 kg at his checkup today and the vet revised his age estimate to 8-9 months.
There's been a bit of a growth spurt, his head is getting Staffy wide and his neck has thickened up so his head no longer looks out of proportion. I don't think my photo skills do his cuteness justice, he's much cuter in person :D