Welcome Tony,
The are 3 types of Centec Vertical head
Mk1 uses pulleys to drive the cutter head
Mk2 uses a shaft to drive the cutter head and swivels to horizontal. (yours and mine)
Mk3 as Mk2 + the quill.
Mk3's go for £300 to £400 and I can't be bothered as the knee moves. The only thing I can't do is drill at an angle and not yet found a need to since I bought it.
Mk2 and 3 were sold at the same time.
You can make a short riser block on a 2A though most owners do without as no one makes them anymore.