Hi,
Do you have the baptism of your Thomas born c1829?
Why I ask is that looking on familysearch, there is a baptism for a Thomas Oliver at Old Swinford on 27 March 1831, parents Samuel and Sarah Oliver.
Old Swinford was quite 'popular' for marriages etc from Bromsgrove, plus it would make sense if Sarah and young Thomas are then in Stourbridge in 1841.
Added: there is a possible marriage for a Samuel Oliver to Sarah Williams
1827 Feb 12 at Kingswinford, St Mary's.
Lisa