Share '7X7 for standing rigging?'

I'd like to redo all of my standing rigging. The plans say to use 6X7, but this seems unavailable in the US. I have found 3/16 7X7 in 316 stainless for a good price. Does anyone know if 7X7 is a shipshape substitute for 6X7? I know that 1X19 is standard now for standing rigging, and that 7X7 is used for running rigging, but it is easy to work with and the working load (on the 7X7) is still over 3…