http://www.gsclimited.com/videotapes.htm
To convert PAL (UK, Australia, NZ) videos to NTSC (Japan, US) and vice versa?, there is GSC in Roppongi:

"Send us your original tape, and a blank tape (you can also buy blank tapes from us).
* Please mention your name, address, telephone, conversion system (or name of countries).
* Please enclose exact payment with package (or send separately by genkin kakitome). Return delivery charge is ¥700 in Tokyo, and ¥1,000 anywhere outside Tokyo (Per package).
* We charge a flat rate of ¥1,500/hour per tape. Any time over the hour counts as an extra hour.
* Process-time is generally one day.
* Only VHS, VHS-C, SVHS, 8mm, Hi-8 tapes."

Tapes can be mailed to:
GSC LIMITED,
Roppongi International Building 1-C,
7-3-12 Roppongi, Minato-ku, Tokyo 106-0032
Tel: (03) 3403-0956
E-mail: sales@gsclimited.com

It seems that the pricing on video tape conversion is going down. Actually what's happening is that you can get this stuff digitalized and put on DVDs. However, I'm not sure if it would automatically be region encoded. Can anyone who speaks/reads/writes Japanese check it out?

Maybe some camera shops do this. Maybe it's called "dabingu (dubbing) service." There are tons of stores on-line that provides VHS to DVD conversion services, like these:
http://www.stl-jp.com/
http://dvd.atw-plus.co.jp/
http://dvd.aicomp.jp/
http://www.soundsmile.jp/
http://www.zeican.com/service/index.htm

and these are just first 5 listed on the net in a search. This ZeiCan only charges Y105 for a tape up to 20min long, Y263 for 60min, Y494 for 120min, and so on.

sorry, I forgot to put quotation marks on everything after "out?". That info comes from another person on another list. I re-wrote the quote slightly so it's not an exact quote.