I recently found a local ad for a used Pearl flute but the owner is describing it as a PF-621 model. I can't find any info with that model number. How old might it be, assuming such a model existed, and would it have been made in Taiwan?

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Well... never mind, owner just emailed me to say they meant to type PF-521. I am finding plenty of info on those, but wondering whether they are worth any more than a secondhand PF-501 these days....