If the issue is the diff why the need for all the parts on the ebay link ? Unless you have those parts missing you should only need the diff related bits ie, diff balls, plates, thrust washer ...
I wouldn't bother with the bronze bush bearings in the 'kit', better to build your g/boxes using proper ball bearings.
These do Ansmann/Team C spares:
http://smddirect.co.uk/index.php?_a=...id=50&page=all
The Ansmann part No. - Team C conversion list is here if it helps:
http://www.produktinfo.conrad.com/da...L_TR02_2WD.pdf