Hi Adam,
As Ray says, those Perthshire "fountain" designs were called Aladdin's Cave, but that name was apparently used only in their early literature. I don't know when the name was dropped. The example in the Sweetbriar site is a triple-layer and is correctly listed as a PP8 design. Your two-layer example is a PP7.
The details of Strathearn weights are well covered in Richrad More's fantastic site:
http://strathearn.smugmug.com/Richard gives the P7 sizes as, "over 2.7 inch to over 3 inch", so your pink weight, at 3 inch, is indeed a P7 and the other one is a P8, being smaller.
Dates are from 1964 to 1980 - regular production throughout all their years.
The high dome on your P8 is perhaps less common but the shapes do seem to have varied quite considerably.