Board Thread:General Discussion/@comment-3392084-20130707145759/@comment-4807396-20130709073014

I can help with that:

The Japanese intro and opening credits in MGS

Japanese Otacon, Snake and Raiden in MGS2

Japanese Solidus' pre-fight speech in MGS2

These should give you a taste of the Japanese VOs in the earlier MGS titles, but they're all over YouTube if you care to look...