Where are you hosting postgres
On the same machine where they are currently storing the sqlite file maybe? It's not that hard to run. A sqlite backup cron is also not that much more work than a pg_dump cron.
if they have only one server, then on that server. If they have a load-balanced front end and central database, then on the database.
On the same machine where they are currently storing the sqlite file maybe? It's not that hard to run. A sqlite backup cron is also not that much more work than a pg_dump cron.