Much less expensive than
these guys and perfectly serviceable is
T.M. Lewin. You do, as always have to be careful you don't color it up too much, and end up looking like a junior catering manager... Especially love their version of the knotted cufflinks, the
barrel links, find the plain knots just slip out anyway...
I wish they had an online presence, to share, but the other go-to when in
Edinburgh is
Ede & Ravenscroft. And the shop is beautiful as well.