dmf vs smf

The father of one of my work colleagues has an octavia tdi 110 on a w plate, and is in need of a new clutch & flywheel. I have landed the job of changing it for him, as the garage he usually uses has quoted him a ridiculous price of roughly £1200.(close to the value of the car)

My question is this, which do i fit, SMF or DMF, and where is the best place to purchase the chosen item? also, I have read somewhere that if fitting a SMF I will need different flywheel bolts.

I have not done this kind of conversion before, so all help and advise will be gratefully appreciated.