Found about the CN330n serial chip.
It's around $3 + shipping on ebay and possibly cheaper on other sites (probably as low as $0.33 or so).
The only issue is that the only datasheet is translated from a poorly made chinese datasheet.
Chinese datasheet: https://datasheet.lcsc.com/szlcsc/1811151442_WCH-Jiangsu-Qin-Heng-CH330N_C108996.pdf
Hackaday info about it: https://hackaday.io/project/162389-ch330n-33-usb-to-uart-info-and-applications
Translated datasheet: https://cdn.hackaday.io/files/1623896947650976/CH330DS1.zh-CN.en.pdf
I did a test with it and it works really well.
Baud rate of 115200 with the Parallax Serial Terminal Demo.spin loaded worked beautifully.
The only thing to note is that instead of DTR for reset, you need to use RTS.
But for a SOP8 package at around $3 + shipping or less, it's quite nice.
Breadboard of it is attached.