I think you should be able to just grab an equivlent x200 off of ebay (possibly with a different wlan card added) - and be safe (as in safe that you can run libreboot, not any guarantees about firmware in all the dark corners, like ethernet card).
I've been considering trying libreboot on my T420s - but as I use it almost every day, it's a bit high risk in case I brick it.
http://minifree.org/product/libreboot-x200/