https://www.yealink.com/en/product-detail/ip-phone-t46u - $150
https://www.yealink.com/en/product-detail/accessories-exp43 - $100
https://www.yealink.com/en/product-detail/ip-phone-t31g
https://www.yealink.com/en/product-detail/headset-wh62 - $150 (plus a $25 adapter cable)