I designed a 1:1 copy of the originals 3D printed in PETG to give it heat resistance, toughness and the little bit more flex that's required to not break on the little fillet on that joins the bottom slat.

Each set is printed, hand drilled and test fit on a set of vents to ensure they don't pop off the slats or damage anything. This could be the only decent repair and saves faffing around with glue, staples, metal pieces etc. I use these on my own Vectra C and they are working great with no foreseeable drawbacks. Thee are other ones you can find and print online but the holes are not in the right spacing/alignment and I found these can be very hit and miss. This version is my own design.

£10 for a full set of 4 posted. Or there is an eBay link if that's allowed to be posted here for more peace of mind: https://www.ebay.co.uk/itm/265732418376

Thanks!Vectra C vent clips.jpg