Wow, you weren't kidding... $179 on Amazon, $202 on eBay. That is insane.
What about this one? http://www.amazon.com/Kit-Charging-Cradle-Google-Nexus/dp/B00GP20PYS/
If you really want to make your own, I don't have the specifications but I did find someone who made a technical model of it.. he wanted to make his own custom dock too. Pogo pins are specifically mentioned. You should be able to get the sizes and spacing from this.