Morris,
The horrible fabricated stand was definitely fitted in 1958.
It seems that in 1959 some time the cast stand was fitted, a definite improvement over both of the earlier stands.
The best feature of the first stand (1954-7) was the mounting, it pivoted on a sleeve captured between 2 lugs on the frame. It didn't wear out the mounting lugs if everything was kept tight.
With the late stand, I drill and tap both mounting lugs and fit grub screws to hold the pivot pin in place and stop it wearing the frame, after repairs, of course.
Trev.