I believe it's more than double but maybe somebody has some real data available. Anyway if I remember Fiesta WRC parts had very short service intervals, for gearbox it used to be only 400 km (it was before last evolution).

I was told by a man running several Fiesta R5 and before several Fabias S2000 here in CZ that the running costs are circa same. Afaik normally it was around 100 Euro/km. I can't imagine how You can push WRC car under 200 Euro. Some very old WRC cars for sure yes but modern ones?