100GbE beyond 40km

How is everyone accomplishing 100GbE at farther than 40km distances? Juniper is saying it can't be done with anything they offer, except for a single CFP-based line card that is EOL. There are QSFP "ZR" modules from third parties, but I am hesitant to try those without there being an equivalent official part. The application is an ISP upgrading from Nx10G, where one of their fiber paths is ~35km and the other is ~60km. thanks, -Randy