Hi Tom,
The tang that is peened over, and the leather sheath usually means it was made on Luzon. What area I'm not sure. Visayan blades normally have partial tangs, wooden scabbards, and often chisel edged blades, beveled on one side only. The time period could be any time from before WWII to now. There's a good thread on Luzon blades on another forum that starts with "R".
Steve