@oristarA,
No, it doesn't mean the same thing.
When you "settle" for something it means that you aren't quite satisfied with it. You make compromises or otherwise lower your expectations in order to meet a certain goal.
Here, I think, by "mate", they mean "to reproduce" -- to have a baby in order to continue your genetic line.
In English "Mr. Right" (or Ms. Right) is the fantasy person someone has imagined as being the perfect partner to marry and have children with.
"Mr. Right Now" is a person you like but doesn't fully meet the arbitrary list of traits that you have imagined for your perfect spouse.