Hi Grumbles,
It looks like her first name might have been Elizabeth (providing her younger siblings had the same mother as her)
The pilot familysearch site finds christenings:
Samuel Owen, 12 Apr 1831, St Julian, Shrewsbury, parents John and Elizabeth
Elizabeth Owen, 14 Feb 1836, St Julian, Shrewsbury, parents John and Elizabeth
Eliza Owen, born 10 Apr 1839, christened 10 April 1839, St Julian, Shrewsbury, parents John and Elizabeth
Seeing as little Eliza was born after the start of civil registration: have you tried looking for a birth cert for her? It would tell Elizabeth's maiden name.
