Baby stretchy sling

I need a seamstress to produce 50-100 baby slings - these would be one piece of fabric so should be very easy to produce. Spec below:

• Baby wrap that’s 20cm wide, 5m long
• Material - viscose or any plant based material such as bamboo
• Weight - approx 400grams per square metre
• Stretch - approx 20% in the cross direction and 30% in the machine
• Material - over lapped and stitched all the way round