Looking for assistance please

Hi all,
It’s been suggested I might find the help I need here.
I recently had a Windows corruption occur so had to reload win 10 on a new hard drive with IT professional son’s help.
I have been a SketchUp user since ‘7’ and stayed through fully licensed product up until 2015.
When the incident occurred I lost the Skp 2015 install registries (I think that’s what son said).
I do not like being effectively blackmailed into a subscription service at great cost, and simply wish to continue using 2015 going forward. I have never once in all the years needed to call upon ‘support’.
Does someone have a 2015 install file they might share with me which I can reactivate with my activation code … or give me any advice that will see me back in control.
I do small drafting jobs to supplement my insufficient aged pension to get by and cannot afford to just rebuy something I have paid for already several times over.

You need the install files for Sketchup 2015 Pro?
I guess i have these on one of my backup disks.

Adding a license to Make makes it Pro.

Thanks gentlemen really appreciated. Will try these ideas in the morning. Hope I don’t stuff it up.
I am totally in awe of both your work! Awesome stuff!