Could be a few things. Do you have experience with switch mode power supplies ?
Is there an ozone smell associated with it ?
How often is the click ? Or can you record it? (sorry to ask again, I'm trying to tell if it's the floppy drive ticking or if the PSU is shorted somewhere).
Ultimately, you have two options. A multimeter and a soldering iron will most likely be essential, and require special long-shaft torx opening tools.
Or, find somebody who does component level repair (soldering skills), and is familiar with undocumented switch mode power supplies. Try TV repair shops (if they exist). If not, then I'm happy to help, but via forum id somewhat limited.
On the rear label it should also denote it's mains voltage (ie 220 or 240V AC). If so it will require the international circuit part references, rather than the more common 110VAC Only version.