this question crops up all the time, and to be honest turbo charging the AGN motor for 2 grand would mean doing most of the work yourself, you're talking turbo, manifolds, downpipe, pistons, rods, plumbing and piping of intercooler/oil&water feeds, sump, ecu upgrade.. i hope that's convinced you that an engine swap would be easier

as said above though the best thing you can do, is sell it and buy a 1.8T if you're after power.. adding the word "engine modifications" to your insurance policy before you're 25 is a complete nightmare (i've only got 6 months to go !!

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sports cat (or de-cat if you're friendly with your MOT tester), full exhaust, maybe a custom downpipe to match, decent air intake and a ecu remap/chip should see you pushing the 140bhp mark.. next logical step after that would be internal mods like cams and head porting/flowing .. after doing all that is the time most people decide to go forced induction.
as for your engine, might get 600 quid for it if you're lucky, more if you break it and sell bits seperately.
toph.