I have to agree with Alan. In addition to being "heirloomed," marbles are small, round, and have relative weight, meaning they're goin' down as far as they can go every time the earth in their vicinity is disturbed. The only conclusion that can be drawn from a group "find," if that's what's pictured, is that none are older than the oldest one found in the group.
That being said . . . there are a couple I wouldn't be comfortable dating to before 1930. Focusing on the nice red & white "9" at right center: the marble to the right of it, the extremely flamey purplish one, looks suspiciously like an Alley to me. Unless it's one of the Veiliglas ones, as you suggest. And the green-based white swirl above the R & W one . . . just looks like a WV swirl to me. Don't think I'd put either of them pre-1930. But that could just be me.
In several places I've seen the ones we generally refer to as Japanese (spidery pontil) attributed to the 1950s, but I've never seen any evidence put forward for or against that. So I have no idea, really. That whole class of marbles (Japanese, German, Canadian, Jovian) has suddenly become a can of worms for me . . .