There is no way for a consumer, buy a new license for $20. Their is program for Register Referbishers that allows a MRR to get a replacement COA, Create Restore Media, etc for $25. (note this is NOT a new license, in order to quality for this the PC has to have a OEM License) and requires a 14 page contract with MS that has all kinds of conditions and requirements on the person
https://www.msregrefurb.com/RRPSite/Templates/RR_ProgramAgre...
>Assuming that's correct,
I believe this to be a false assumption on your part. The License does not magically disappear if the Restore CD was lost, especially given the fact that I am not aware of any system on the market today that actually comes with a physical Restore CD anymore