You can buy new Japan Fenders direct from stores in Japan. Here’s a guide I wrote.
MIJ is a big step up from the Made in Mexico Fenders, basically close to (and sometimes exceeding) Made in America Fenders.
I would say your best and easiest bet is probably with Ikebe Gakki in that thread, I can totally vouch for them, bought from them locally many times. Others on the forum had good experiences with them when ordering from the US as well.
Now. All that said - there is nothing wrong with Made in Mexico Fenders. You can get excellent instruments that way too, but I would advise trying them in person, as they are less consistent than MIJ or MIA.