I had the same thing happen to my speer. What I ended up doing was finding some regular old nylon and sewing myself a new hammock bottom.

So what I did was took a seam ripper/utiilty knife to "unsew" the strapping, took the old bottom out, made the new one to size, with hemming and velcro, and then re-knotted the ends and then re-attached and sewed the strapping.. it wasn't that terribly difficult to do and I would definately prefer that to a bottom with a rip in it - which might fail at a very inopportune time.