Getting around the reference issue with companies that have a "no-talk" policy is a challenge. I went through the same thing a few years ago and missed out on good jobs because I couldn't get the proper referrals. Think about former co-workers or manager's that might not be affiliated with the company because they retired or move onto other opportunities. Use social media to network out to folks you used to work with and find out who's not there anymore. I would also call the HR department at those companies and check if they have implemented an employment verification process.