@Taos Taz I think that you have a number of native tarantulas to that area and there is really no way to tell what species at that size. Spiderlings are very dull and nondescript and don't show any of the colouring/markings that your adults do. Your Aphonopelma in the United States are harmless, especially at that size.
What are you planning on doing with them?
@Taos Taz No, there is nothing wrong with keeping him.
They need a smallish enclosure, about 4x their leg span. They need to be fed about once every five days when they are small. They should have a damp area of substrate and a water dish if possible. Don't worry, they don't drown. Even though they have come from outside, it would be a better idea to feed them captive bred insects to cut back on any possible parasite/chemical transmission.
The same care applies to all the species that are native to your area. They are slow growing, but females can live well into their 30's.