Hi Sean
not done one of these recently but have had a spate of them at the VW Audi specialists where I work. The fault is normally caused by the chain guides and I believe there is a modification which might be reflected in the differing parts prices. Top end rattle is common on these, normally caused by low oil press and a clogged strainer. This time I guess the low press was caused by the pump/chain failure. In my opinion genuine parts are the only option in this situation. Hope this helps.
Dave.