Depends on which 33" tire you choose. Most 33's are 12.50 wide and that would require an 8" rim. But there are a few 33's out there that are only 10.50 wide and you could run them on a 7" wheel.
The 12.50 will fit on a 7" wheel, but you get a balloon effect on the sidewall, and that isn't a good thing when it comes to off-roading, because the sidewall comes into contact with too many things that can injure it when it's ballooned out on a narrow rim.
That and with a stock Jeep wheel and a 12.50 wide tire, the tire is going to rub the leaf springs severely when you turn. Doesn't matter if you have 10" of lift, its because of the backspacing on the wheel.
The correct wheel for a 33X12.50X15 would be a 15X8 with a 3.75" backspacing.
'87 YJ, 4.2L built and bored, 8" of lift, 8.8 rear, AX15/NP 231J, Tom Woods drive shafts, Flat fenders, 12,000LB winch, Custom bumpers, Rattle can paint job. Never completed...