ISO 8601 week determination with adjustable beginning?

[DaveH76]

Although I recognize that ISO 8601 specifies Monday as the beginning of the week, I would like to be able to have the far superior year-end behavior of the ISO 8601 week determination method coupled with the ability to set the first-day-of-week to Sunday as our industry has historically adopted. This could be accomplished via either an additional setting within the ISO 8061 standard, or as a separate standard (perhaps "ISO 8601 Sun").