£15 you say ... might drive down and have myself a little scavenger hunt
Is your vent still broken btw, it's probably an easy fix, I had mine apart the other day and it sounds like the little lip thing has just popped out of place.
Got my garage to whip it out as he had some plastic trim removal tools - rather than me launch at it with a screwdriver. So I never actually saw it out.
Was weird as normally they slide left or right easily. Mine locked to one side and if I tried to centre it - it was spring loaded and kept pulling to the side again.
£5 in his hand sorted it !