People who have studied scripture so extensively that they know the old way of spelling sometimes use that spelling, not thinking about that others don't take that much time for study, so they spell Paul Shaul.
Many people in Paul's day didn't consider pork food. Paul was intent on making the gospel accepted by pagans who felt that if it meant what they ate, they preferred their old diet. Gospel was important, not diet. Paul did not say that you may not use food as a symbol of what God wants of us. If pork who ate refuse symbolized uncleanliness, Paul did not say that abstaining from unclean meat could not be used to symbolize that. God had suggested we do that, Paul pointed out the point that was important was the spiritual point, you could eat that meat and still be clean, spiritually.