How To Enhance Stamina And Ejaculation Duration?

My mate is 35, he has fathered a number of kids, was a sexually active young man early, but has since dedicated his self to me and our family. 6 years ago when we got together we stayed sexually active, sessions would lets for 1 to 2 hours easy. Now the firmness is there, but he ejaculates quicker; maybe 10 minutes oppose to 30 to 45 minutes before. He has tried Cialis, it works pretty good, but is very costly and not covered via insurance. We would like to know what is currently the best supplement that's available online or stores that we can get to enhance his stamina and duration. We do all of the foreplay which is great; just looking for ways to make the sessions longer. Also we would like to know out side of a vacuum pump is there any supplements that actually work to increase both the length and girth of his penis. We would like to try something that has been proven to yield results but not something that can harm him.