A new stock coupler will show a terrible amount of slop. Why? Because it has to accommodate two planes of mis-fit...something only a universal joint can do without slop, and Porsche didn't want to go to the expense of a universal joint here.
Many have press-fit a tight-fitting bronze set of bushings in a stock housing..but this limits one plane of possible mis-alignment and can lead to internal trans issues...much better would be to use the tighter-fitting 914 plastic inserts, at least this way it can be "forced" into the alternate range of motion ( as a universal joint would allow) with a little bit of "give" that bronze" won't allow.
There was a long-ish discussion on this...I'll see if I can find and repost..
- Wil
EDIT--> here and the embedded threads
New shift coupler - loose?