I just bought these, and they're very much like fabric, so I don't know how effective they'll be long term (as I just put them on brand-new pillows):

https://www.amazon.com/dp/B071J45BWR/ref=cm_sw_r_cp_apip_UehJ1k5fuFeHP

I've had these in the past and they work well, but they do make me a little hot at night. They don't seem to be as bad as what you've described:

https://www.amazon.com/dp/B002AQLPQA/ref=cm_sw_r_cp_api_QKBZzbJSKQQJP