Looking For Single .040 Nylon, or Florocarbon, Not Wound Strings

I would like purchase single .040 nylon, nylgut, or florocarbon strings to use for a Low G string in a GCEA tuning on my baritone uke. I have some sets of regular Baritone GCEA tuning so I could just substitute one of those strings for low G. I've already tried Just Strings. No luck. Thanks for any information.

Bill
bvh

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