Wow, that is a prime candidate to swamper. Keep it as it is with big 4x4 tyres, and the VW arch kit. Comfort, cool, and practical as a Camper.
Bare in mind it might sit lower at the back once it's been converted, so wait until they've done their work, before purchasing any springs, but you might find if it still sits as it does in that picture once fitted out, that 30mm might not be enough to level it out.
There should be quite a few 30mm spring/17" wheel pictures, due to many owners running Devonports, or the standard 17" GP Steels, and 30mm is a common mod because VW offer it at point of sale.