2012 galaxy jumps out first gear only.urgent help pls.

[m.abid]

hi all im knew to this forum and have just joined hence my first post.
i have a ford galaxy 2012 .6speed manual.2.0tdci.
i use it as a mini cab and im out of work because it keeps jumping out of first gear into neutral.happens may be 2 times out of ten.
doesnt matter even i keep it pushed forward it still does it and i get a nasty thud on my wrist.also i noticed that when i start it from cold its almost impossible to select the reverse gear i have to put it in 2nd and role a bit and then it allows me to choose reverse.
but once the engine is warm then i have no difficulty in selecting reverse.
my main cause of concern is the first gear when it jumps out i can hear gear cogs making a loud noise as if they were not seated properly.
once it has jumped out of gear then i put it back in first and it seems to work fine.
all the other gears work properly.
1.checked for play in cablesand found them to be ok.
2.clutch operation was checked by a mechanic and he said your clutch is fine he reckons its the syncro ring faulty and worn out.
3,car has done genuine 86000miles.
the gear box specialist tells me that they have open it up and costs could be Ã,£600 to 1300 plus vat.has any body elese had a problem similar to mine i want to know before i take it to the gear box specialist.
pls point me in the right direction.
also is there any specific section in this forum that deals with gear box problems.
thanks.