I remember trying lots of places for a small sink, and I think it was an AAMer who finally pointed me in the right direction. [broken link removed]e in Belfast might be just the business, I have the Sintespun3 (355mm is slightly wider than what you suggested but it might suit). It was £79 stg approx + VAT. They don't normally deliver, I emailed to ask, but if you know anyone making an IKEA trip maybe they could pick one up for you. If I recall correctly the Kohler sink is undermounted, this one is not, so that may make a difference to you.