Hi Stephen,
I have a J. Bromhead mentioned in High Street Miatland in 1850 occupation hairdresser. Also listed in Greville's 1872 directory as a hairdresser High St Maitland.
A Joseph Bromhead rented a small portion of land in High Street in 1870, at the area known then as the embankment, corresponding to where the Hunter River used to run beside High Street prior to 1913 flood. This is on northern side of High Street, eastern end, roughly opposite the Currency Lass Hotel which still operates. The source for this is the 1870 rates book, held by Maitland City Library.
According to 1901 Census, J Bromhead kept a store 2 doors west of the maitland Town Hall.
According to 1924 rates a William S Bromhead, High Street, Maitland , occupation "CPS"?
Try Lindsay Watts 65 Britania St Umina NSW 2257 - appears to be a descendant