It’s cheap So a good project to get your teeth into. Audi parts are expensive so good used parts will make it worthwhile. Before you throw too much money at it, find the engine code and check out threads relating to it, there’s some horror stories for certain engines.
What year of car do you have? Ticking could be timing chain or HPFP if you have E888 engine commonly called a TSi. I have the 2.0litre version and changed the complete chain kit and tensioner at 42000 miles as a precaution.
lots of these engines across VW, Skoda, SEAT have self destructed...
I don’t know any part numbers but if you source them from a reliable parts supplier, such as Audi or TPS, they will be the latest revisions. Trying to buy them cheap from EBay is not where I would buy them. Your chosen repairer should tell you where he buys his parts.