My own genuine Profab swingarm off my 1980 CR125RA. Uses all stock hardware. Will also fit 1979 CR125RZ with 16.5" shocks I believe. This is the arm I made the reproduction ones from which are all sold out now. As you can see it has had a repair on the left side which has held up fine. Unfortunately there is now cracks on the right - I didn't even know this until I came to take the pictures.
Price: 175.00 GBP plus shipping.