cluch-do I still have one!!!

[npca-big red]

I own a 1978 G60 patrol, petrol that I bought 7 months ago not running for $1000.  After alot of time and a bit of money its now going great but for one thing - the gears grind alot!!!  With the car at the traffic lights and I go to put it in first and it grinds.  When I change gears, I double clutch and it still grinds a little.  I had it half submerged in water and when out the clutch didn't even seem to work.  The clutch however does not seem to slip and its about $800 Australia dollars for a new one!!!!  Does anyone now what the problem is, or would it be better to get a second hand clutch and gearbox from the weckers?