I think the best thing you can realistically do is find a team better than your team but by a small margin and make a deal with them that you will always be around to scrim with them. They gain the benefit of a constant scrim buddy, you gain the benefit of playing those better than you (the only way to truly get better).
When cbear and I were on our various mid-level teams we became "brother and sister" clans with CB/ducky/smaka's team. They were better than us, and usually beat us, but we learned a lot from them and on the nights we beat them, we felt awesome. It helped us improve beyond measure. Later, when players on both teams left we formed together and became MMM and went into invite.
EDITED THIS SECTION CAUSE IM DUMB
Also take a look at trihards and HRG. Last season when the Tri-hards did not bring clock to lan, they more or less became the designated scrim buddy for HRG. HRG had the benefit of always having a team to keep sharp on, and the Tri-hards had the benefit of playing the best over and over. Cue the next season and the tri-hards became the second best team.
moral of the story: look to play up, but marginally, it isnt realistic to expect to play the best teams, but if you can find a consistent scrim buddy that is better than you, you'll be on the right path