It does not answer your question directly but, please have a look through this thread by @genchiro.
Likewise I recently came across some YT videos that might be of use to you for shopping in Japan, here, here and this one by VeksTCG. I believe @veks also made a recent trip to Japan, so maybe they can share more info personally. Mostly long form content that you can explore before your travels.
Success and wishing you a safe trip.
Cheers!