Do these woofers look right on these Dunlavys IVA's?

Yes they look correct, I had a pair back in the late 90,s.

Dunlavy on the model  4s had 3 different versions. The big changes were changing the woofers from Morel to Seas to Scanspeak.  The Scanspeak required changes to the crossover and probably to the damping to maintain the Q that John preferred.  Along the way Dunlavy sent me 2 new sets of midranges that looked identical but sounded slightly better to my ear. Tom

Correction..the woofers were Morel, Vifa and finally Scanspeak..Tom

I believe Tom may have this correct.  I owned a pair of Duntech Princesses which were the older sibling to the DAL IV/IVA.  Mine came with Scanspeak woofers but when the DALs were introduced they did not.  I assumed John changed to a less expensive drivers.  If he did change back to Scanspeak woofers near the end of their production then I expect those may offer somewhat better bass.

If you are close enough to pick these up then an audition should put your mind at ease.  I think all of Dunlavy's designs were very good if not exceptional.

Those are diffuser cones................kidding. I actually saw these and wondered the same thing so thanks for asking the question. I have no interest i these so good luck!