I use a logitech k810 on my desktop, although its bluetooth (but so far had no issues
). picked it up for ~$69 some time back. Off the top of my head there is a dinovo mini (thumb keyboard) which can be found for around $50-75 on sale, There is a bluetooth model and a unifying model
Edit: also the Lenovo N5902 (multimedia thumb keyboard) which can be found for around $35 on sale last i checked
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