I'm not really into reggae, (not to mention Japanese reggae) but Doggystyle (Inushiki) is a really fun band, and they're heading a concert at the Kyoto Metro on the 30th. It starts at 8 PM and the advance tix are 3000, at the door is 3500.
Here's the info page:
http://www.inushiki.com/schedule.html#1130
I'm pretty sure you can get the tix at Lawson or wherever.
If you're interested in going, I'm pretty familiar with the area so we can go meet for drinks before or after or whatever!