Hi: I tried to answer this from a mobile phone app but it's very buggy so you may see this answer from me multiple times. Sorry (in advance!). Fujikura has something they call USLP that might be adaptable for your work?
This supplier can provide the probe you are looking for
https://www.prizmatix.com/
You can contact the supplier they can provide the design according to your requirements. Here you have the flexibility to select the fiber features (core diameter, NA, type of fibers, and so on).