Time would be about a month because I would have to take the mould and pick up the resin casting from Dave Brian who lives twenty miles away from me and I visit only fortnightly. Cost would depend on whether or not you need bridge wing supports to be cast with the top of the superstructure. Please email a photograph of the model to roger@coastlinesmodels.co.uk and let me know where you want the casting to be sent (if outside UK mainland).
The Mercator model is of Normandie as built whereas the CM model (still available) is of the ship after refit to enable her to compete with the more powerful Queen Mary.