I have all the parts except the FPGA myself. It's about 80% done, laying in the drawer at work.
The SD card socket was indeed tricky to obtain. I finally got one from another DIY electronics kit (
ebay link). This kit also contains a couple of other parts (pushbuttons, serial port, etc) which come in handy.
I'm interested in building more than just one Minimig, so if you come across any good offers, let me know.