I'll admit here to much preferring stitched eyelets to grommets. I've had to replace both metal and plastic grommets in the past, but never stitched ones. I use machine stitched ones like these for garments: [img]http://www.diceyhome.free-online.co.uk/KatePages/Costuming/Kate's_Klobber/eyelets5.JPG[/img]

You'd probably be better off hand stitching eyelets over a metal reinforcing ring for a tarp as they would need to be larger than corset lacing holes! Some UV protected nylon tape, or tapes sewn from off-cuts of the tarp fabric, sewn into loops and stitched to reinforcing patches might be your best bet here, both for durability and weight.
_________________________
Kate XXXXXX
Mad sewing witch!
http://www.katedicey.co.uk