Broken latch of ribbon #3 ( 2 pins missing )

The pins are there, but there is now nothing to apply pressure and hold the pins against the contact points on the flex cable. And whatever the other 2 pins connect to, they'll almost certainly be required.

Other than buying a cheap faulty device or logic board for spares, it's highly unlikely you'll find a supplier of the connector itself. And even if you did get one new or old, fitting it without the right soldering equipment and a lot of magnification would be next to impossible. The pins are so close together that even solder paste and a hot air station would be tricky and involve perhaps more than one attempt.

Still, if you can get an old board to use the connector from, and find someone or a TV repair shop that has the equipment to do the job, you may get it repaired. Some iPhone independent repair centres that can be found on the net and advertising on eBay claim the ability to repair to surface-mount device level, so for a modest fee may be able to help. Otherwise a google search should show other repair centres that boast the equipment and skill to SMD repair. Basically, if they repair motherboards, iPhones, mobile phones, etc., and say they can repair to SMD level or have the ability to replace BGA components, then they're tooled up and skilled enough to do the job.

Not much help I'm afraid, bad luck and I hope you find a solution.