I have tracked down exactly one photo of a cab forward pulling a passenger train and the cars were heavyweights, not streamliners. And yes, the Lionel Daylight cab forward was a fantasy scheme but one of, if not the best such scheme(s) Lionel has come up with.
I doubt you'll find a Daylight cab forward in the aftermarket. Legacy GS-4s appear rather more often. If you are looking for steam power that is your best bet, IMHO. There's a mine of information on these Daylight trains here and on the related/linked pages: https://spdaylight.net/Welcome.html
Someone more informed than me might tell you that with the GGD cars another engine, maybe a diesel, would be more or just as prototypical. But it's your train.