This series from Samtec might work:
http://www.samtec.com/ftppub/pdf/idsd.pdf
They don't offer a three row connector, but it appears that you'd be able to place a double row and a single row together. I would contact one of their application engineers to verify this.
They have online pricing, I think you could get both cable assemblies with stripped/plated ends for about $20.
They do have three row board mount connectors if you were going to build a PCB. I think it's the SSQ series.