Another name for Margaret was Peggy.
The Peggy Blasdale marriage seems likely - a bit far away but the date fits perfectly and there are no baptisms recorded for Richard and Peggy in Notts.
In 1841 she was a widow described as a Grocer and was living with sons James and William in Sandiacre. 6
1 Georgina Lyons, BT. Based on 1st child.
The Church of Latter Day Saints, International Genealogical Index, www.familysearch.org/, RICHARD DOAR
Spouse: PEGGY BLASDALE
Marriage: 23 NOV 1812 Arnold, Nottingham, England.
Nottingham Family History Society (NFHS), www.nottsfhs.org.uk, DOAR Richard BLASDALE Peggy ARN 23/11/1812
Nottingham Family History Society (NFHS), www.nottsfhs.org.uk, ARN 14/08/1785 Peggy John Margaret BLASDALE
FreeBMD Online Index of BMD, England & Wales, www.freebmd.org.uk, Deaths Dec 1842
Doar Margaret Shardlow 19 370
6 Ancestry.com Online Census and BMD, www.ancestry.com, 1841C.
7 Georgina Lyons, BT. Based on 40 at death.
8 Georgina Lyons, BT. 1831 Burial of Richard Doar 1 Dec aged 40.