How Much is this coin worth?

I have a mexican coin thats from 1967. It says Estados unidos mexicanos. Heres a link for fron side. http://viewmorepics.myspace.com/index.cfm?fuseaction=user.editAlbumPhoto&albumID=407747&imageID=7433788 and heres the back side http://viewmorepics.myspace.com/index.cfm?fuseaction=user.editAlbumPhoto&albumID=407747&imageID=7433779 I dont know if the link works