See Castle Street East 1 to 15 &c in London Addresses database
No 9 Castle St East Land Tax 1784-1796 Jane Harforth / Morning Herald ad 5.6.1788 Mrs Harforth's, poulterer, No 9 Castle St, nr Berners St, Middlesex Hospital
Will PCC 1803 of Jane Harforth spinster late of 9 Castle St now of Oxford Market dated 5.3.1803 mentioned Elizabeth Gard dau of John Gard late of Harley St & Elizabeth, also mentioned Elizabeth her niece wife of James Alexander Muir of Bird Street, St Marylebone. Jane Hartforth bur 11.3.1803 St George Bloomsbury. (A Jane Hartforth was bapt 25.2.1721 at St Giles Cripplegate of Thomas & Eliz). John Gard = 1787 by lic St Geo Han Sq Elizabeth Bray. John Gard bur 24.6.1790 St Marylebone. James Alexander Muir of Holkham Norfolk bach = 25.2.1797 St Marylebone by lic Elizabeth gard wid otp. Elizabeth Muir bur 24.11.1807 St Marylebone. James Alexander Muir accomptant took admon of Jane Harforth's will 4.4.1811