I thought I'd update this thread in case others ever need to know...
I originally thought the hatches were made by Goiot
but I was reliably informed that Fountaine Pajot
fitted Goiot portlights
to the Bahia
and Lewmar hatches. Back on the boat it clearly says 'Lewmar' on the hatches. Oops! The two large bridgedeck hatches (not escape hatches) on my Bahia are Lewmar Coastline SZ40. The official lewmar replacement seal was the same price
as the seal sourced by the local chandlers in Spain
, except the seal from the chandlers was long enough to do two hatches. Sorted!