MY son has what’s called an American Stafford-shire Terrier - he is a big dog. When he was about 1 year old he started getting really arrogant and pushing our other dog around - he would not listen and/or come when he was called even though he had been trained to do so.
He needed very firm discipline and a focus of that discipline - for us it was a light aluminium tube which he got a few good wacks with. I don’t like to do this but he needed it and is the best dog since - all I have to do is mention ‘The Stick’ and he comes over and sits down next to me. As good as he is I would not trust him with small children - he is just too big and could easily hurt them plus if he knocked them down the hunting/fighting instinct might kick in.
He is a great dog but you have to strict not mean and wary not complacent.
Good gosh, an aluminum tube?
How about a loosely rolled newspaper? It isn’t about the pain, it is about the gesture, the physical display of displeasure.
The loosely rolled paper allows for noise and a harmless (whooshy) whack, and even a harmless expression/release of the owner’s anger, yet covers all the bases of a firm expression of displeasure with a dog doing something intolerable, and for which other methods haven’t prevented him from doing.