Leaking water ballast bags

One of the bags on my DG-300 is leaking. I took it out of the wing
and confirmed that it's leaking at the seam an inch or so from where
the plastic inlet clamps in place (the wing root end).

Repair options seem limited -- but I'm tempted to try to fold over the
seam of the ballast bag that's leaking and clamp it externally to try
to isolate the problem. Has anyone tried this?

I'm sure I'll be advised to bite the bullet and buy new bags. That's
a likely result and, so far, through past threads I've found:

http://www.easternsailplane.com/catalog2/water.html (they advertise
Smiley Bags for $360 a pair for DG-300's)
and
http://www.clipper.com.au/ (they can make bags if I give them
drawings...).

Any others?

Thanks,

Eric