Hi Colin!
Good news! I think the actual Crown and Thistle building has been found. I mentioned it to a local historian and he did some research.
The house is now 2 Bridge Terrace, the first house (quite a substantial one) over the brige, opposite the Ship Inn.
It wa built by James Murray about 1818. In 1833 he sold the property to William Henry and on his death in 1860 was bought by Mr Murray Stewart, a local landowner who owned it till 1896. During this time it would have been let to various tenants including Thomas Birtwhistle Tait, innkeeper and to David Brackenridge.
Best wishes Mary