+1 for GPE - great service, and very reasonable shipping.  For the 4 connectors, shipping will probably be around $5-$10 - Ed's a great guy to deal with. Link to GPE 0.1"" connectors http://www.greatplainselectronics.com/Category-68.asp.

You can also try Big Daddy, and I have purchased from them as well with great service.  http://www.bigdaddy-enterprises.com/.

Either place has the total for the 4 connectors at about $5.  Marco is more expensive than either, and shipping from Marco is what it is."