Engine flush? I can't think of anything you could put in the oil (and if it isn't in the oil it won't clean the pickup pipe) that would clean this without destroying the bearings.
If the pickup mesh is blocked, it is with items that won't dissolve in engine oil: usually bits of sump sealant that have been squeezed out of the joint when the sump has been put back on, which then go brittle and break off, dropping into the sump. So when you replace the sump, make sure you don't put too much sealant on the join.
Replacing the pipe is easier than cleaning, but cleaning shouldn't be difficult. Slosh it around in a dish of paraffin then dry it off once it's clean. The debris is mostly held in place by the suction of the pump and should easily come away with backflushing.
The pipe is a component of the engine, and the engine (ASV, AHF or whatever yours is) is common across many VAG cars. You could try some of the forum sponsors, such as Sere Motors.
By the way, there are three ways you can determine exactly what your engine is.
Engine number = engine code + serial number. You'll find it:
* Stamped onto the block at the join between the bellhousing and engine block, near the oil filter.
This is pretty difficult to fake and will tell you the installed engine type and serial number.
Looking from the nearside of the open bonnet, the engine number is difficult to see, under the engine cover and a lot of water hoses.
Here it is in close-up, but still in the shadow of all that pipework.
Brightening the image shows up part of the number
* On a
sticker on the cambelt cover
Here you can just see the edge of mine, sticking out from under the engine cover. This is looking from the offside of the bonnet.
The engine code also appears on the build
sticker, which is stuck into your service book, and is also stuck to the floor of the boot underneath the carpet.
Looks like this:
Heres's what my build sheet looks like. The dot-matrix characters can be a little odd
(I've removed the last bit of the VIN code, which is the chassis number)
