Can anyone identify this roofing tile for me?

[unclemark123]

Removed my chimney last weekend and duly dispatched my parents to our local roofing wholesaler - they could not match my existing tiles, but did have a close equivalent. They did advise that they were slightly smaller, but I had to make do as a temp measure, although they are not the best of fits. I need to find 20 odd to match the existing size exactly. They are Marley tiles, but I am unsure of the 'model' - they are very similar to the 'Anglia'. Being 1960's they must be imperial. Not too bothered on colour as you cannot really see them, and I'm sure they will weather in - or more likely if I buy used tiles they will already have weathered.