If they aren't displaying the information, I would take your business elsewhere. Halfords sell their own brand and Comma x stream longlife, both of which are silicate. phosphate and amine free.

I had this issue with Subaru coolant. I couldn't obtain it anywhere. People on the forums said that it was even a problem at the dealers, and they were handing over the counter Shell radiator fluid instead.

In the end I went with Quantum longlife, a VAG brand. This had all the specification I needed, and is the same as the types I mentioned above.

I did have the system flushed though, as I was changing from green to nuclear dayglo pink.