What Isofix base will fit these car seats? I have this pram already and struggling to find what Isofix base that would fit.
I am sorry to say the original Adbor car seats are not compatible with any Isofix base. They are made to be secured with the 3-point car seat harness only. There is no Isofix base to get to match it with the car seats from the 3in1 system. I am sorry I couldn't help more but the manufacturer simply doesn't offer that possibility, the base for those car seats. They are the simplest ones just for the system to have some.
My own personal preference would be to get better/safer car seats with a base, but those, unfortunately, you'd probably wouldn't be able to use on this pram's frame.