With DPF delete pipe and remap which cost about £700-850 fitted will see a claimed 220-230 bhp and 330ish lb torque. If you want more you need the PPD race injectors and a bigger turbo. If you want a plug and play turbo you can get the stock turbo internals enlarged to the same spec as a Turbo Dynamics stage 2 turbo as used on PD130/140/150/160 engines as it`s basically the same turbo but clocked at a different angle with a different manifold design.
Stage 2 MD376
Hi flow 2275 spec compressor wheel, cnc machined compressor housing, 360 degree thrust bearing, cut back turbine blades, lightening of turbine wheel for faster spool up, modified V.N.T. turbine housing, uprated turbine seals. Other blueprinting modifications.
If you want anything bigger your looking at getting a custom manifold made to get the turbo to fit but any VNT turbo can in theory be made to fit all the way up to a hybrid GT3067V.