I sail a Nacra 16ft square solo which is the same as a 5.2 only with 2 inches shaved the hulls. As mast length I am unsure but with the large main sail its most likley longer.
I can right the boat solo but you need wind to assist which should be present to have put you in your situation. I use a righting rope that runs under the tramp along each hull to then form a v shape with a bungee pulling up the slack.
Your mast needs to be well sealed and it will float amazingly well. Stack out from your ceter board 50 deg or so and wait. The mast will raise a couple feet off the water and stop there. Hang on and wait as the wind will blow the boat around until it catches the sail and up she comes. I have been over 3 time so far and had no trouble. I wiegh 100kgs so I reccomend you try it out with help near by just in case...
As to the mast it can be done by having the rear stays attached with the boat pointing dowhill on the beach and up she goes. Grab the front stay and step off. If you have a bridle you can also run a rope from your front stay through the bridle.