Non Combat Headband Question

According to the rules, non-combative characters are to wear a green headband. Would something like this: www.etsy.com/listing/51349636/solar-headband  or this: www.etsy.com/listing/51951503/celtic-knot-head-wreath-in-white be acceptable if they were made of green leather? And if so how light must the green be? Is sage or olive light enough? Or must it be a bright lime color? Also, how does this work in the winter time? Can you wear a green hat to stay warm to indicate the non-combatant status when it starts getting cold out?
Thanks!

The problem I foresee is that people may not recognize it as a green headband.  In the winter the headband should be worn over the hat. 

To clarify what Mike said - there should be an obvious distinction between costuming and a headband.  It may be a tad unfashionable to be wearing a lime green headband all the time, but it's better than accidentally getting into combat, and hurt!

The same would apply to white, red, and yellow - they should be very distinct, and clearly a status indicator as opposed to costuming.

Okay thank you very much for clearing that up for me, I appreciate it.