Hi Gareth,
My great great grandfather was the said John Richardson who owned Kirklands. I'll run a check through the family records to see if there's any mention of yr ancestor, but I doubt there will be, as it's mostly family letters to/from the next generation. John Richardson, who was an Edinburgh lawyer, is always said to have moved to Ancrum to be near his friend Sir Walter Scott.
Minto (Elliots) was the next 'big hoose' up the road from Kirklands, and the families were close friends, so it's entirely possible that your ancestor moved employment from the one to the other.
Minto was demolished, but Kirklands still stands & is, I think, once more owned by Scotts.
There's also a collection of Richardson family papers in the National Library of Scotland. I've only trawled through them for stuff of direct interest to me, but they may well have something of interest to you
Andrew