I've got a laser cut design of stacked layers for the Raspberry Pi B+.
It includes openings for the GPIO pins and for the official pi camera (& Pi NoIR).
Also included is a 3D printed mounting for the official cameras.
Step 1: Laser Cut Files
I've left this as SVG as I have some issue with outputting to PDF on my laptop ATM.
It may not be absolutely perfect but it's close. I hope to update over the next few weeks to make a few minor changes on 2 of the layers.
You should be able to import the svg file into anything you can use for a laser cutter anyway.
I've used M3 x 25mm fixings for this. They're a tiny bit long but work well.
Step 2: 3D Printing Files
I've attached both the STL file and the SolidWorks part file so that you can make any edits you wish. I've thought about moving the position off-centre but I'm not sure I need to yet.
You may also want to remove the 2 "claw" type parts that I've added to grab the tabs on the top of my touchscreen.