Hi and welcome to the site! Tyson's a cutie. Curious, what's the difference between a Victorian bully and an English one? Because Tyson looks like an English, maybe bigger?
As for the raw. You're doing great! Has he had any poop issues ... too soft maybe? If not, that's fantastic. It's one of the challenges of starting raw.
Starting with chicken is very common. And you should be able to see changes soon. With my bully, Stig, it only took a couple of days for his hives to disappear. But don't take that to heart though, it's different for everyone. Since his feet has pustules, it may be after they're healed that you'll see a difference. I say give it a week and see if any redness has gone down. Since he hasn't had any loose stools and other signs, he's probably not allergic to chicken.
Keep on doing what you're doing with his paws, sounds like you're progressing. Wondering also if it's winter in your area and if there's salt on the ground. Stig's sensitive to that too, so we wipe his paws clean after every walk.
You don't need to add organs right away, but if you would like to start with small pieces at first. Heart isn't an organ in raw terms. Lung and stomach are in the middle, some say they are, but some say they aren't. Those that def belong in the category are spleen, liver (max 5% of the diet!), kidneys, etc.
It's against the law to sell green tripe in normal grocery stores, so I source them from raw feeding stores, farms and other rawfeeders. Whereabouts do you live? Maybe I can try to find a community for you. There's no firm set amount of green tripe you can give. Some give a spoonful each time. My boys sometimes get a whole meal of green tripe if that's the only thing available.
And I think 99 cents/lb of chicken is a bargain. Lucky! I aim for less than a dollar for anything too, especially pork, chicken and turkey. I get half my meat from ethnic grocery stores as they carry various parts. The rest I get from local rawfeeders who sell.
G'luck! Let us know if you have any other questions.