FJ2 is a correct part number suffix for the dash trims and instrument cluster surrounds and I'm not surprised it isn't a known paint code. SEAT don't paint the trims in-house. They are bought in from their supplier pre-painted so it's very unlikely the actual paint mixture is publicly known.
You can order replacements pre-painted but if you wanted to know about the actual paint used it's very unlikely you'll find that information anywhere.