Im of the opinion that the risk of any damage to the pump is more or less nothing, as the oil is a lubricant anyway, and not much went in anyhow.

Seals wise I genuinely dont know, as I dont know if they are likely to be harmed by engine oil as Ive never tried it, but it seems unlikely, especially in a short period of time and when so diluted, besides, any harm in that respect, is already being done if its been pumped about.

So personally I would happily risk it, but then its not my very expensive car, its lee's, so its his decision ultimately as no one will give him a definitive answer I suspect.