Andy,
Could you please give a little more detail as to which leon you have?
I presume you mean the 110 tdi se leon? In which case the injectors will not fit because they are from a different type of diesel injection engine, the PD range of engines specifically.
The 130 turbo however will be a direct fit to the engine and all you will need is the red turbo outlet pipe and the turbo to make it fit with your current piping.
If you do go ahead with this upgrade, You may want to invest in a 130/150 turbo inlet pipe to allow enough air into the turbo, these are between £20-£50 on ebay.
Hope this helps.
S10EAT