Kudos to CCS Disability Action, who operate New Zealand's disabled parking permit system. They have a very easy process to apply for a New Zealand permit online and have the permit sent to your accommodation (or in my case, brother) to await your arrival. All they need is a scanned copy of whatever the local equivalent is where you live - in my case the "blue badge".
A pity the UK can't reciprocate with this.
OTOH, it is possible to use UK (and other EU) permits throughout the EU and usually airport parking will let you use the disabled space, but take your blue badge with you on holiday - they usually ask you to let the attendant know as you are leaving.