lining kit

Evening all, This could be a silly one, but does anyone know what these holes here are for on a lwb ? just making sure they aren’t any sort of slam vent. Also does anyone know if you can buy covers for these or what they would be called? many thanks, Jason

I had my 2014 T5 panel van converted, and now have the ply side linings, plastic panels, floor fittings etc. - all in really good condition. Any advice on where's a good place to sell them, and how much I could be looking for? I also have a twin front passenger seat... Thanks