Hi Mama-
The legal limit is .08, so anything over is considered illegal. Depending on his dependency, his use, and his metabolism, it may or may not be high for him, but it is too high for legal driving.
As far as rehab, some insurance companies do cover it, but you need to go to a 30 or 60 day treatment or a 30-60 day outpatient program. Many times, they are court ordered. But as far as your brother needing help, until he is ready to be sober or thinks he has an issue, there will be nothing to fix. That sounds terrible, but addiction is just that- a terrible disease. And until a person is ready to hear, ready to change, and ready to stop what they are doing, they will not. They have to believe that they have a problem and want to change it themselves, even if they need your help.
What you can do is offer resources- names and locations of rehabs in your area, rehabs that his insurance covers, and the willingness to support him when he is ready. I suggest you, as a family member what wants to help but doesn't know how, to go to al-anon. Meet with the families regularly, get support, and get tips. Tough love is hard on both you and the addict, but it really does work.
Good luck
He can do this, and so can you.
-E. M