Numbers for 10.12.6?
I am trying to find Numbers 5.1 or a version later than 3.6 that will work with Mac OS 10.12. Any help deeply appreciated
It wants me to update the OS to 10.14 which I can't do because I use audio software that is only compliant to 10.12. It's a bit of a pickle
Yes, I expected that App Store would want you to upgrade to get the latest version of Numbers, but I thought you might find an older version available via the Purchased list.
If you are having trouble, download the iWork 09 Trial from Apple here and then see if you can upgrade it to which ever version from this Apple page, https://support.apple.com/en_US/downloads/productivitysoftware
If the method I propose above does not work because you are starting from a trial version or the update fails for whatever other reason, and proposed resolutions by other members don't work out either then I recommend you contact the AppStore support linked on this page, https://support.apple.com/contact.
Apple will provide you free support for this issue as it is related to a previous App Store download that you made in the past but can't find. They should be able to provide you a link or resolve it one way or another.