We have an experience very similar to yours. While everything else is normal, he was not babbling and at 9 mo, qualified for EI. He is 16-mo now, and deemed a perfectly intelligent, healthy late talker. I have loved my experience with EI. He still qualifies and will continue even though there is every expectation that he will be fine just like many of the other replies here have indicated.
What to expect: getting started was a bit of a production, and it took a little more than a month for services to start. I have LOVED my experience with the therapists, counselors, etc. They WANT so badly to help. The service is there and if your child qualifies, they want your child to receive full benefit of it. I self-referred (based on an SLP's recommendation on this subreddit, actually.)
We only used SLP services, and they came to our house for an hr a week. They worked with him, but it was really directed play and a chance for me to learn how to support him. At this age, they're gonna do what they're gonna do on their own timeline, and we just support them as best we can by talking, playing, reading, etc. My biggest concern? If he has some kind of learning or developmental delay, we'll deal with it, but I want to know that I'm doing absolutely everything to make sure he has the support he needs from us. EI was wonderful about making sure that he did/does have that. If you're assuming the worst (I'm like that too,) EI will help you feel like you're doing everything you can to help your kiddo. The director (or counselor, I'm not sure her title,) has an autistic son, and confirms that just from an hr or so of observation, he's just not autistic, nor does he appear to have a learning disability.
Additional notes. Start with sign language. I'm not kidding and cannot emphasize enough how awesome it is in general, but even more awesome for late talkers. My kid has a vocabulary of over 35 words in sign-language, and has very recently began talking ("mama", "dada", "kitty-cat", and "meow"). First, you can get see if all the logic is there when they begin signing. Second, it's ridiculously adorable; third, these late talkers need a means of communication to prevent melt-downs; fourth, they say that signing helps advance verbal vocabulary. He picks up 2-3 words a week on average, and is limited only by my not looking up EVERY word he points to to teach him. He loves it!
You can pm me if you want. I was in your position at 9 mo and the only one at all - period - who championed getting him help. They are so incredibly supportive and if you qualify, you have a really great ally. I wish so badly that I could pay them bc I would love to show them my appreciation for hearing me and supporting my son when I was the only voice in the room.
:)