The information I have on Hawkes is from the New Langwill Index. They show:
1860-62, Hawkes & Co, Cumberland St, Pimlico
1862-75, Hawkes & Co, 33 Soho Square
1875, Hawkes & Co, Leicester Square
1876-89, Riviere & Hawkes, Leicester Square
1889-95 Hawkes & Son, Leicester Square
1895-1930, Hawkes & Son, Denman St, Picaddilly Circus
Hawkes & Son
Additional Images of a Brian Boru bagpipe stamped Hawkes & Son can be seen at The National Army Museum website. There is no doubt that Henry Starck was the maker, which pretty much rules out Hawkes & Son as bagpipe makers.
Well, I don't know what to say! I was in the process of updating the website and had moved on to the Henderson page when I received an email with the following pictures! The tuning pins are stamped "Hawkes and Son". The bagpipe does not look to be the work of Henry Starck.