Stopped by the Electronics Dept. while I was at Wal-Mart this afternoon and found the PS3 version of Saints Row IV: National Treasure Edition in the $19.96 bin. It scanned at the same price.
I didn't check the 360 version but it was also on the $19.96 shelf, so I'm assuming it's the same price.
There's a chance that this price could be YMMV, but I wanted to post anyway on the off chance that this price is universal.
With the PS3 version, the DLC is on the disc. It did not come with a DLC insert. Not sure about the 360 version.