There's no way to take individual plays that far back and scrobble them to last.fm
When I need to scrobble in bulk manually, I copy the entries (Send To - > Clipboard with fields title, album artist, album and time set in Tags (2)...'send to clipboard' tags) to a csv and use
this to upload, but it's been a long time and I really can't advise on the details of how to use it beyond knowing I've done it in the past and it works.