Man, it's got to be up there. There's lots of games to look through where a QB got 6-7 INTs, but they're still accruing a few hundred yards and usually a TD or two. Pick six stats are hard to find, but from what I can tell the career record is 6 (held by Peyton Manning). I guess it's a rarer event than you'd think. I doubt anyone's ever had more than 2 in a game.
Here's one game I found that's arguably worse: http://www.pro-football-reference.co...7210090oti.htm
Dan Pastorini: 3/21, 31 yards, 0 TDs, 4 INTs
EDIT: Oops, that Manning record is for a season. Looks like the career record is 35 (Favre).