Hello TheCatLady!
Glad to hear you enjoyed Seers Isle. :)
Actually, chances are that Seers Isle OST is already available on the streaming platform of your choice. You can also buy a copy of the digital album from Bandcamp. Here's a handy link that will lead you to the album page on the most popular streaming services:
https://fanlink.to/SeersIsleOST
Thanks!
Geoffroy.