They are out there, and you can use one from the MF or 1V engine, too (your engine is an ME).
Here are some useful part numbers for searching:
Bosal 783-309
VAG: 191-253-087 (ME), 191-253-091-E (MF), 191-253-091-BG (1V).
Keep in mind, the 1V one (from the Ecodiesel) has a tiny catalyst in it, so it would likely cost more.
The turbo engines (MF and 1V) have that little elbow that makes a tight bend out of the turbo housing and goes down and lines up at the same spot, with the same dual spring attachment, so that is why you can use those too.
If all else fails, you can bolt pretty much any VAG 4cyl exhaust manifold on to the head and just use whatever downpipe that engine used. You can also I think use a downpipe from a low output gas engine (like the RV 1.8L) as it will attach to the manifold but is a slightly larger pipe so you'll need to adapt something on the other end (or just run the larger exhaust all the way out the back.... but it won't make it any more powerful).