I've had 3 roadstars and cannot recall a plate giving the date of manufacture on any of them.
You could deduce the approximate date from the Electrical system inspection sticker that lunar apply the next inspection date should be 12 months later than original, which would have at been the end of the construction. Failing that the NICC certificate should give you an indication.
I've just checked my own vehicle. The NICC certificate is not dated so is of no help. The only clue is from the electrical system safety sticker.