Cast net makers- Help wanted

[Whoofa]

Haverford, ATS etc, no longer stock vinylon or Kuralon in size 20/6 - 6ply. Can any net makers help me in sourcing some, or an alternative that will suit for sewing reductions in a cast net. I'm after a twine that will not slip, and that doesn't require a double knot. Any help or alternatives would be appreciated.

Thanks in advance