whats your budget exactly? I got my 150bhp AUM for £800 which was expensive but I was impatient lol, but the conversion probably cost me around £2800-£3000, you need a lot more than just an engine

Try and get your hands on a rear ended mk4 or a3, take then engine etc out and sell the rest for parts and the conversion will pretty much buy itself, depending on what you start with you'll just need a sport cat/de-cat, downpipe, bigger bore exhaust (eg 16v jetex system) and other small bits and pieces
If you wanna do things on the cheap I'd advise getting an AGU, its 150bhp same as the AUM but only has the K03 turbo as opposed to the K03s in the AUM. Its easier to put into a mk3 though as its cable throttle so theres no messing about with putting electronic pedals into the mk3, and you can swap to the K03s later on for more power
