Jim's Steaks on South Street would be my pick!

I like Jim's Steaks or Steaks on South, a few blocks from the Historic District.

by far the best cheesesteak in the city is at a place called John's Roast Pork in pennsport (snyder ave). It's not terribly far from old city (historical section) and would probably be a $8-12 cab ride. If you really want to stay close (within short walking distance) you can try Jim's Steaks on south street or Campo's Deli on market street. however, i will note that those are "touristy" and can have crazy long lines at times.

Sonny's Famous Steaks on Market near 3rd street is pretty good, and Jim's Steaks on South St is worth the walk (also hit up the Philadelphia's Magic Gardens while you are there)

So close to historic area try Jim's Steaks on South Street or Campo's Deli 214 Market Street. I lived in Old City and on South street and both are good choices. Honestly though you should take the $9 cab ride to Pat's King of Steaks 9th Street & Passyunk Avenue or Geno's Steaks 1219 S. 9th Street (or both) for a legit cheesesteak. Yes can be a bit touristy but you won't be disappointed. 

Try Sonny's Famous Steaks at 228 Market Street