Most vinyl manufacturers will colour match to Pantone – Most will have a moq of at least 50m/100m, some as high as 500m dependant on range of vinyl. Most of these (if not all) will be colour matched on cast vinyl as it is uneconomic to colour match on calendered vinyl – There will usually be a higher price for these colour matched products compared to standard cols. This may make this uneconomic for a single van.
If you only need a few metres would suggest going down a ink match route and screen print in sheet form – This should give solid matched colours to any pantone requirement – If screen print is not an option then you could digitally print enough square metreage (and use overlaminate for vehicle use) and then cut on a plotter as if it were standard vinyls … however some pantones can be difficult to achieve using CMYK printing.