Yes, go to a kite supplier for braided Dacron(tm) = polyester line. Per weight it is 30-50% the strength of dyneema /spectra. It doesn't stretch and doesn't absorb water.
We could go on and on about minimal UV resistance, probably not included in 150lb test line available for $.025 /ft = $.08 / meter.
"Mason's line" could be about anything, the reason there are different reports about it. Let's wake up to the fact that it is not made to be load-bearing. That it might bear any weight is incidental to its use in construction.