Sous Vide Strip came out medium well, what did I do wrong?
130 degrees is certainly the temperature to aim for, I'm thinking that it's the pan sear that did it. 1 minute in a pan is actually quite a bit for a thinner steak (at 6 ounces I'm thinking yours were maybe 1/2 - 3/4 inch), certainly enough to add 10-20 degrees or so to the steak's temperature and make it medium well.  

As for how to avoid it there's a few things:


Get a thick steak: a thick steak can take a minute in the pan without cooking much more
Cook to rare: if you want to use a thinner steak cook it to 115 or 120F instead of 130F, that way the sear will bring it up to the perfect temperature
Use a torch to brown it: A chef's torch would give a good, quick sear without cooking the steak as much as a hot pan
Sear the steak first: it's not as good as searing after, but then you will get your perfect temperature
Cook the steak, then let it cool, then sear it. Your steak will only overcook if the temperature goes over 135F