if you can make a /etc/fstab entry for your filesystem, then you can configure pam_mount using the same options as the fstab entry and it should work.
for the actual encrypted filestore, i’m using gocryptfs. it’s a more actively developed alternative to eCryptfs: mostly a drop-in replacement. there’s a lot of options here: dm-crypt over a dedicated partition is probably what a cryptographer would recommend, everything else is making tradeoffs (e.g. leaking metadata like file size/directory entry count) for better UX elsewhere. read the wiki to pick the best for your needs :)
on the off-chance you’re using NixOS, i configure these parts here:
Could you please share a general outline for configuring something like this?