Fred Holder
Since your have three Super Nova 2 Chucks, I would recommend the Nova Titan Chuck it is a large solid chuck designed for use on large lathes and for larger projects.

This solid 5” diameter chuck with it’s larger jaw capacity, and unique 3 hole jaw slide, is capable of handling much larger projects than the SuperNova2 Chuck.

The Titan can also take all the Teknatool chuck Accessory jaw sets in the range (although with it’s larger size, we recommend appropriate larger accessory jaws as the perfect match)

Most of the above is from the Teknatool website. I have two of the Nova Chucks in the 5" diameter range. The first one I purchased when in New Zealand in 2003 and the second one I got a year or so later when it had been updated. They are excellent chucks.