According to the CrowdSupply page, no keyboard is included ("As everyone has their own keyboard preference, no keyboard is included.").
Like a lot of people, I really like the keyboards on ThinkPads. The "classic" USB keyboards are hard to come by and/or expensive these days, so I'm currently planning on getting one of the current-generation USB keyboards and gutting it:
http://shop.lenovo.com/us/en/itemdetail … 1FF88E33C7
It's just a USB keyboard, so it should be plug-and-play.
Otherwise... whatever you'd like. The heirloom laptop is, IIRC, shipping with the bluetooth version of the keyboard I linked to above. I don't see the point of using wireless, though.
And, as a disclaimer, this is just my opinion, which definitely doesn't carry any official weight.