The material is from a sheet of Mylar sail material, I can’t remember the actual website however it’s the same material as the 1m IOM yachts (international one meters) use which there is a dedicated website for with those sails pre-made... we just ordered a roll of it. That should be easily googled.
The “tape” is sail makers fabric tape. Which you will need to finish the sail as well and giving the sail the correct shape. Both tape and sail material are from the same site.
If these are a pain in the backside.... you can locate some lightweight tight weave waxed cotton and make your own with the aid of a sewing machine, which is what I did with my display model in the end, although she’s never sailed with that rig it was more for presentation rather than practicality.
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