I'm looking into the plug and drill option.

The wheels are 40 mm offset, and adding a spacer will move that by about 20mm, so I'll check on ET20 wheels next week.

I want 17inch rims, because I want to fit bigger discs and ideally BBS/lattice style, and after spending the last 4 months looking, I haven't found a single wheel.

The alternative is going to Image wheels, and they want the best part of £2000 for a set of wheels.