I used to order a few things from Herschel before they were bought out.   At that time I called them up about something and they were pretty helpful.   I see they have a toll free number listed, give them a call.   Throw a few questions at them and it should be easy to spot if they know what they're talking about.   The fact that it's a toll free number is probably a good sign they are legit.   I doubt a scammer would have anything more than a burner phone number.