Hi
1861 census
There are two entries for Allsops Down, looks like two seperate houses as you thought in the 1871, entries as follows:
RG9 Piece 687 Folio 4 Page 1
Allsops Down, Broughton, Hants
William page Head marr 75 Farmers Bailiff b Salisbury, Wilts
Joan Page Wife Marr 59 b Crawley, Hants
Sarah Goddard Visitor Unm 74 b Brathfield, Hants
Allsops Down, Broughton, Hants
James Stone Head Marr 51/56? Carter b Broughton, Hants
Ann Stone Wife Marr 51 b Broughton
William H Stone Son 17 b Broughton
William Scammell Boarder Unm 16 Plough Boy b Wellow, Hants
Anne