Carl,
This pair would be sexually mature at this size and age, but it would be critical that the female has good body weight. Do you have a way of weighing this female? Greens are spring breeders and should be introduced in the late winter or early spring. Photoperiod and temp reductions before introduction will help cycle the reproductive systems. Males are usually introduced to females although the importance of this is not well known. The smaller male probably will not be necessary, but that would be your choice, and his maturity would be borderline at that age and length. Let us know how it goes.

Kelly