I couldn't give an exact amount off hand, but from 
previous experience I would suppose it'd probably 
exceed $50-100.
The best site for shipping rates from Japan is here:
http://www.post.yusei.go.jp/p_guide_2001/index.htm
You can see what the prices would be for a variety of 
methods, so long as you can guesstimate how much 16 
VHS tapes would weigh. ^_^;;