He'd be better off with a set of 20" LTZ wheels if he has a 6-lug. They're pricey because they're limited, but the 20' Tahoe wheels are plentiful. A used set in good condition will run you less than $500 on craigslist, ebay, etc.
I bought those 5 new Jeep takeoffs for $240.
I bought those 5 new Jeep takeoffs for $240.