Even better - https://tex.com.tw/products/shinobi?variant=16969883648090 - I've been using one of these since they came out and they're fantastic.

I used to have one of the old thinkpad external keyboards - http://www.notebookreview.com/notebookreview/lenovo-thinkpad... - and I used those until they broke and I couldn't find more.

I haven't used the unicomp ones, but I can wholeheartedly recommend the shinobi.