Hanwha and Sth Korea in genaral experienced defence exporters these days, used to dealing with the requirements, demands and quirks of foreign countries. I doubt they freak out when the customer wants something, even if it sounds strange to them.
This was my concern when PM Abbott decided Australia would buy off the shelf subs from Japan back in 2013. Not that the subs were bad or unsuitable, but that Japan would have a constitutional crisis every time we wanted something. They'd agonise and delay rather than immediately work towards a solution, because they were not experienced dealing with complex arms exports.