(edit: when I say "cost" I mean the production cost)
Well, a pound coin is used more than once, and there is tax applied on every time it is used, so it'll pay off for itself in a relatively short timespan, imo. Plus, it pretty much beats counterfeits, so loss from that is gone too.
Problem with 1 kurus was that it wasn't used often, the monetary value was small and that it had no anti-counterfeit stuff. Also, people were melting it and selling it. You can't really sell a broken or write-protected rfid chip for much.
Since most money is held in banks, electronic transactions, etc - the question is more the 'value of supporting this denomination in currency to the economy' than the cost of a coin.. Like of $100M USD worth of tax/federal reserve interest revenue is generated from $10M of $100 bills that cost $15M to produce, it's not really a loss, but a business expense...