I didn't want to order the special 11mm brass raspberry pi standoffs from Adafruit at $9 shipping, so I decided to print some that will do the job. These are 11 mm high, and snap in to the screw holes. They are not as sturdy as the brass ones, but if you print them at a fairly high quality (I used .2mm), they should be strong enough to keep the hat from flopping around.

Printrbot

Simple Silver

No

No

.2mm

30%