I changed to ppsu too, using spectra bottle as the head is compatible with most wide neck flange for direct pumping and also pigeon/philips avent teats. I fit mine with philips avent natural teat too! https://shopee.sg/product/242594539/5732034154?smtt=0.0.9
You can buy back Avent PPSU bottle natural series. I just got them recently.
Maybe you can try hegen?