vintage Syracuse china plates w/ round Aberdeen china thistle mark

Lot of five vintage china plates with a round mark for Aberdeen china. We've been told that these are actually Syracuse china (old ivory type) but haven't been able to track down this pattern at all.

There are four of the plates about 8" in diameter, and one plate about 8 3/4" in diameter. All look nice, no trim wear or noticeable scratching, no chips or cracks.