Awwww man, I have the same issues with my HDi.
Rattly/squeeky DMF and sliping sometimes
in fact it hasn't slipped now for weeks for some reason.
It will be a £600.00 job and I was looking at an LUK clutch and DMF (about 280.00) and labour (about 320.00) it may work out a bit less if the labour works out well.
I am convinced though now that the occasional slipping is also caused by oil seeping from the crank seal and contaminating the clutch aswell as the actual 'wear'. In this case, when you dismantle everything you will be faced with fitting a new seal too (not sure if a costly job or not?).
I sometimes regret buying my Diesel, I have got the clutch/DMF/crank seal AND a rear engine mount that has torn through it's rubbers and it's a big mount and looks expensive because the drive shaft goes through it aswell, all this lot has wiped out any savings I get from the fuel economy (which also has not worked out like I thought)
I fix all that stuff I would have to keep the car and get some use out of it, if things were any different I would change the car tomorrow and bid it a fond fairwell