A picture of a part set of Mystery #167 in blue for your file if of use.
Has anyone suggested that this might be made by Roscice? Back when I had no idea of the I.D of most of my glass I thought it was made by the same manufacturer as the creamer also pictured because the colours are so alike. I realise that this isn't proof positive but it certainly seems a better match than it is to frosted blue Walther although I've seen this set advertised as Walther several times.