It looks typically 50's/60's Scandinavian. What suggested Orrefors to you? I'm not disagreeing, necessarily, but again Orrefors, and the other main suspects, are usually marked, and the lobed effect is unusual for Orrefors. I'd try some of the companies who did the brownish colour like this and usually marked their products with just a label, such as Aseda, Smalandshyttan, Sea Glasbruk.
Holmegaard did lobed pieces, but I would have expected Nick or one of the other Holmegaard experts to have identified it if it were by them, and, again, it would be marked.
Good luck.
David