hope for Ingmar Relling sling chair?  

I have an Ingmar Relling for Westnofa black leather sling chair which was in decent condition until yesterday. Unknown to me the cotton canvas sling began ripping in the back along the seam, and then suddenly continued its tear all the way to the front along one arm. I'm not sure what to do, the canvas does not look repairable.
Please note that this is not the Siesta sling chair, for which replacement canvas slings are still sold. My chair is similar, but suspended from four corners of a wooden base, exactly like this model: https://www.1stdibs.com/furniture/seating/lounge-chairs/ingmar-relling-westnofa-brown-leather-sling-lounge-chair/id-f_919253/
I thought I might be able to take the old sling to an upholsterer to try and reproduce it from scratch. It's sewn into four leather cups which are all in good shape. But on closer inspection, the sling has middle layer of padding and a leather trim detail that makes this "reproduction" idea seem ambitious.
I'm wondering if anyone has a better idea, perhaps knows a more precise model name for this chair, or better yet knows of a source for the replacement canvas. It would pain me to throw this away, and I'm also not sure who else would want to deal it. My preference would be to bring it back to life somehow, as it's a very nice lounge seat.
Any suggestions are greatly appreciated!