You can buy surround kits even at Parts Express...
Unfortunately, what you don't know is how replacement surrounds will affect your suspension compliance.
Also, replacing the surrounds is a difficult thing, because you are talking about a foam-on-paper (I'm assuming paper cones on those? I'm not familiar with them) joint, and I have a feeling the glue will be the strongest part of it... probably difficult to do.
You might contact the company, and see how much you can get recone units for, you could even recone them yourself at home, which would no doubt be an easier effort.
I don't know what your time is worth, but I'd contact the company and find out what replacement woofers would cost, what having recones done would cost, and also researching (once I got the T/S specs from the company) suitible aftermarket raw-driver replacement drivers for them.
Because I have a feeling this is one of those spittin' and swearin' end up wreckin' the damn speaker driver anyway type of ventures...