Chuck Waterman here:
I highly recommend Rendaiji Clinic to anyone who needs to get PCR tested and get the results back the same day.

https://goo.gl/maps/KrcUfGaKfrcNmh4z5

I arrived this morning just before 9 AM, let them copy my passport, filled out information on an uncomplicated form, got my PCR nasal stick up the nose and was out of there within 30 minutes!

I had to go back at 6PM to pick up my results, but - hey, same day is same day!

33,300 is a little expensive, but that includes A) the test B) getting a bilingual test results form and C) getting it processed and given to you the same day you are tested.