Fantasy Baseball Gonzalez/Cabrera trade?

I am trying to acquire either Adrian Gonzalez or Miggi Cabrera from teams in my league. I am willing to offer up any combo of these players for them: Colby Rasmus OF, Matt Joyce OF, Todd Helton 1B, Placido Polanco 2B/3B, Darwin Barney 2B/SS. What do you think would be a good offer, or if it's not enough. Thanks