Surgenors/ Sargeants

Hi,

I'm looking for any information in regards to a Surgenor family that would have lived in Randalstown, County Antrim. Peter Surgenor married an Elizabeth Campbell (according to his WW1 record) in 1900 in Randalstown. However I cannot find that marriage cert. He went by two different names it was either Peter Sargent or Peter Surgenor. I found his first marriage to Susan McIlvena in 1891 here: https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1890/10712/5905258.pdf  It lists his father as James Sergeant still alive working as a servant. I found Peter in the census in Ballygarvey, Antrim in 1911 which gives his year of birth as 1871. Would anybody be able to help in possibly tracing his father James? Or finding a birth for Peter or even his mother's name. Although it's an uncommon surname I thought it would be easier to find but it's turning out to be more difficult than I thought. I've managed to find loads on his wife's side but it's basically empty for him going backwards, looking forward to hearing a reply, kind regards Dario