https://twitter.com/hashtag/lockercodes
Keep an eye on the people who contribute on this feed and follow them. I'm also like you, in that I only play mycareer, and some advance warning to you, that you'll be continually disappointed.
Locker codes this year focus pretty much solely around Pink Diamond this player or Emerald that player. I've only been able to get one code that gave me vc, and that was a random code. I got 150vc.
You could try #AIRCRAFTCARRIER which was the last one released to celebrate the new park for the flyers. I managed to unlock a pair of Tony Parker lightning shoes!! Although they weren't even unlocked (not that I'd wear them, but still...) and were only worth 1000vc anyway.
Have you got the app? This is stingier than last year as I never got less than 1000/day in 2k14, but this year with player cards you can come out of it with next to nothing. I got 450vc today and getting over 1000 is a rarity.