I have personal experience of starting a niche record store with a friend. We were both tired of the music we wanted not being available and decided we'd do it ourselves. Neither of us had any idea about the music industry. We both put in $500 each. Every dime of that was used to buy the initial inventory. We had no money to have a website built (circa 1999). So I learned how to use MySQL and PHP and built one. During the years we ran the business, there were many conversations with artists and record labels. We sold compilation albums where other people licensed individual tracks from labels and arranged them together onto a CD. We even had several discussions about starting our label, but stopped short of that.
My brother made a song with 10 yearly listens and I can find it on there.
Also Bandcamp is a thing. Very few dinosaurs or really, super niche artists are on neither platform.
I applaud the effort at legitimately trying to get a copy. However, sounds like an opportunity still might exist. Small record labels are always hard pressed for cash. Maybe there's a business deal to be made. I'm sure they would be open to licensing the music to you. You could then release the album yourself, or maybe a compilation album with tracks from other artists in the same style of music. Now you have the opportunity to bring that music to a wider audience based on your interest while maybe making a little money on it as well.
This is HN after all. Maybe there's some new website you can make that allows cash strapped record labels to distribute the music legitimately using some new programming language of the day. You could then write up a Show HN and let us all know. We might even be interested.