Seven now. This should not even be the goal of the defending Premier League champions. To be blunt, if Man United had acquired a manager along the lines of Mourinho, Guardiola, Ancelotti, Pellegrini, Klopp, even Rafa god damn Benitez the goal would be to win, or at the very least challenge for the title. I'm not saying all of those names were available (some certainly were) but that's the calibre of manager a club like United should've aimed for, not a clogger like Moyes.
It doesn't matter if Ferguson picked David Moyes. He may have picked Cantona, Keane and Ronaldo but he also picked Bebe, Djemba-Djemba and Kleberson. It took him ten, TEN goalkeeper signings (Bosnich, van der Gouw, Culkin, Taibi, Rachubka, Barthez, Goram, Carroll, Ricardo, Howard) before United finally had a solid keeper in Van der Sar. He's not infallible. He picked Moyes because he's his mate, not because he's any good.
United have to qualify for the Champions League. They have to, because the loss of revenue and status would be highly damaging. Once you're out, it's very, VERY hard to get back in... and as a Liverpool fan, I know all too well it's not as simple as you might think. I don't think you can flippantly say "It's only X points" when you consider the teams you need to chase down. Arsenal, Chelsea and City are all nailed-on, and that leaves one spot. You've got to beat Liverpool, Everton, Spurs, Newcastle and Southampton to get there. You need each one of them to smurf up. Given that most of these teams have actually beaten United, it isn't looking good.
Now is the time to gamble. If they don't hit 4th this season, the title will not be at Old Trafford for a long time. They need a smurfing huge transfer window. I mean a Chelsea or Man City level transfer window. Get 3 first team quality players and make a post Christmas charge. No decent players will want to touch them with a bargepole once they're out of the CL - again, as a Liverpool fan I know all too well. See Diego Costa and Henrikh Mkhitaryan. Even Moyes shouldn't be able to smurf it up if United spend £50m+ in January. Right now he is doing things like rushing back a half-fit Van Persie and he looks desperate. I think his players know it.