Is it possible to break into an elite boutique after Internships in Corporate banking + No name M&A boutique?

Hi guys,
I am a non - EU student graduating in late 2017 from a target BS in France (think HEC, ESSEC, ESCP). I am a CFA level 3 candidate, having done two internships related to corporate banking/credit analysis roles in top tier corporate banks in France (think BNP, SG, CA, Citi, HSBC, etc.).
Recently, I received an internship offer with a potential employment from a "no name" regional M&A boutique (10-20 deals/y, value ranging from EUR 10m to EUR 75m) in a major continental European city (think Frankfurt, Paris, Milan...). I will probably take the offer.
So my questions are:
1. I am aiming at a graduate position in 2018 at a top boutique in London (e.g. Evercore, Moelis&Co, Jefferies, PJT....). Is it viable to land an offer from one of those boutiques considering my background?
2. I will be 27 y/o in 2018. Is it possible to break in as a first -year analyst at 27 y/o?

Any recommendations, thoughts, and perspectives are highly appreciated.
Thanks a lot.