I bought some SpinFit CP800-L eartips from Amazon.
Currently listening to my Audio Sense T180, while watching "Travels By Narrowboat" on Amazon Prime Video.
Was using the CP800-L tips - they seem to be about the same size as the large tips that came with the Audio Sense earphones.
But, I've just switched to some long narrow bore, triple-flange tips that I ordered for my Etymotic ER2XR - but they weren't the correct tips for that earphone.
They work well with the T180 earphones, if you don't mind the deep insertion of the Etymotic tips -
https://www.etymotic.com/consumer/accessories/er4-new/er38-18cl-4sx.html