Help wanted with the origin of the surname HOPLA.

It appears to have first appeared in Pembrokeshire in the late 1700's

Stephen HOPLA. (b) 1762, Grove, Pembroke; (bap) 1763, St. Michaels, Pembroke; (d) Dec 1822; buried: 28 Dec 1822, St. Michaels, Pembroke.
Married ELIZABETH COSCAR, 30th Nov 1786 at St. Nicholas, Monkton, PEMBROKE.

They had the following children.
(1) JOHN STEPHEN HOPLA.(b) 13 Aug 1789. (d) 16 April 1840.
(2) JAMES HOPLA. (b) c1791; (d) c1800.
(3) THOMAS HOPLA. (b) 1792; (d) September 1838.
(4) MARY HOPLA. (b) c1797; (d) c1799.
(5) GEORGE HOPLA. (b) 1799; (d) 1863.
(6) JAMES HOPLA. (b) 1800; (d) ????
(7) WILLIAM HOPLA. (b) 1803; (d) 1896.
(8) STEPHEN HOPLA. (b) 1805; (d) 1849.