Yes, those numbers mean nothing to Lincoln Office ... they are for the National Office that Willow linked to.
Remember that Sleaford District could be any of these parishes - do not necessarily expect that it was in Sleaford town-
Anwick, Asgarby, Ashby de la Launde, Aswarby, Aunsby, Byard's Leap, Billinghay, Blankney, Bloxholm, Brauncewell, Burton Penwardine, Cranwell, Culverthorpe, Dembleby, Digby, Dogdyke (from 1895), Dorrington, Evedon, Ewerby, Great Hale, Haverholme Priory, Heckington, Helpringham, Holdingham, Howell, Kelby, Kirkby Green, Kirkby la Thorpe, Leadenham, Leasingham, Little Hale, Martin, New Sleaford, Newton, North Kyme, North Rauceby, Old Sleaford, Osbournby, Quarrington, Rowston, Roxholm, Ruskington, Scopwick, Scott Willoughby, Scredington, Silk Willoughby, South Kyme, South Rauceby, Spanby, Swarby, Swaton, Temple Bruer, Temple High Grange, Thorpe Tilney, Threckingham, Timberland, Walcot, Welbourn, Wellingore, Wilsford.