Ive seen an artists concept of a modern CBX using parts from a few different bikes and the original engine but with more displacement. Ill go digging through my reference material and see if i can find it.
The CBX was not a big seller, there were new in the box bikes for years afterwards once they stopped production in 1982.
I'd rather see an Aprilia RVS 8 from two RVS 4's. Like the Morbidelli V 8, but current tech. The bores could be smaller to narrow the bike, because do you really need a two litre V 8? The RVS 4 makes 201 crankshaft h.p. Say, 1.5 litres. Kinda makes the H2R Kawasaki envious, I think.