There is certainly no town called Floors, but there are farms or places called Floors near Cookney in Aberdeenshire, Penpont in Dumfries-shire, Kilmaurs in Ayrshire, Newton Mearns in Renfrewshire, in Grange in Banffshire, near Strathaven in Lanarkshire, and near Auchterless in Aberdeenshire. There's a headland on the Aberdeenshire coast called Floors Craig, and a Floors Loch near Castle Douglas.
There could also be spelling variants - for example there are streets with 'Fleurs' in their names in Elgin, Forres, Stirling and Glasgow. There are a Fleurs in Cupar, Fife, and another just outside Coldingham in Berwickshire.
There could be others, of course, which existed in the 18th century but no longer do.
None of these places are in or near Sutherland in general or Dornoch in particular.