Get a pd130 turbo and have it made into a hybrid, it will cost you not much more over what a reconditioned turbo will cost ! I see you spent some dosh making your a4 as bling as possible so it would be wise to spend a little more on the right ingredients...hybrid turbo, 0.216 nozzles, pd intake and a chipped ECU will unleash up to 170 Bhp without detrimental fuel economy ! I tell you a souped up VE AFN engine feels much better tuned than the pd130 engine and they are bomb proof and rev higher !
£150-200 chipped ECU with 170Bhp maps, £150-250 for nozzles and £150-500 for a turbo will give you more power than modern 2.0Tdi + none of the drawbacks !