Kristy you can buy HP split X2 keyboards on [https://www.ebay.ca/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311.R4.TR9.TRC2.A0.H0.TRS0&_nkw=hp+split+x2+keyboard&_sacat=0|ebay]
or [https://www.amazon.com/s/ref=nb_sb_noss/147-4590547-5344548?url=search-alias%3Daps&field-keywords=hp+slpit+x2+keyboard|amazon] . this video shows how to tear down the split to install the key board
https://www.youtube.com/watch?v=tasyRTA1ZjE
Hope this helps