Pins are 2.54mm pitch, find then in 40 pin bars, male and female, cut in desired length and make plugs.

http://www.ebay.com/itm/10x-40-Pin-Male-Header-0-1-2-54mm-Tin-Square-Breadboard-Headers-Strip-USA-/150838016410?hash=item231ea5799a:m:mVjzkp-X5wBYTLm_gkxxZUw
http://www.ebay.com/itm/10PCS-40Pin-2-54mm-Single-Row-Straight-Female-Pin-Header-Strip-PBC-Ardunio-/180974322541?hash=item2a22e9036d:g:VDQAAOSwbsBXkHSd