Hi Shelagh,
Well it seems that Maria Harbon married again in the 1st Qtr 1886 at Salford to either a Joseph BUCKLEY or a John Hughes Jones. As both of these are fairly common names, it is difficult to be certain what happened to her after that. However, a serach of the 1891 Census for either of these two gentlemen might reveal which one she married.
HART was probably her maiden name and quite possibly her stage name too, though I can't trace her marriage to William James HARBON in England or Wales. As she was from Banff in Fife, it is more than likely that she married in Scotland.
Her death is not listed as Maria/Marie HART on any of the theatre records that I have, and I suggest that you try and find her on the 1891 and 1901 Censuses before proceeding much further with her theatrical career.
William James HARBON (born 4 Qtr 1847) appears on the 1861 Census working as a jeweller with younger siblings Emily & George and parents James and Sarah, James being a shoemaker and the family residing in one of the courts off High Street Birmingham.
The big problem will be to find the stage name which William used. Once you get your Gales free trial, search for the name HARBON and see if anything turns up, likewise with Marie (or possibly Maria) HART. If Maria carried on working after her second marriage, there's a chance she will appear in "The Stage", but less likelihood of finding William in that publication.
By all means get back to me if you get stuck. You could also try joining the Theatre_UK Mailing List and asking on there. For details see here:
http://freepages.genealogy.rootsweb.ancestry.com/~jassie/theatre/index-page3.htmRegards,
Maurice