I'm guessing the most plausible things you can remember here would be the amount and a more accurate time of transaction, this ca narrow down the search a lot further. You can try linking the action to at other event you did before or after at the time, so for example if you were taking an exam when you did this or attended a wedding. With the address you can use any available tool that works now to check that with the passphrase to know if it's valid.

If you do get the amount and it's less insignificant, it will make the 'I told you sos' more fun'.

Also do you think at that time you would have left some clues for you now to find it?