Hi Ken,
I had a tripod like that a while back, I just cut three pieces of cord(cloths line) and tied between each leg about 6 inches up and it prevented them from spreading, not pretty, but was quick and easy and worked just fine.
Dave
Cloths line is a good idea; or three ends of keychain, hold together in the center with a keyring and attached on the legs with keyrings.
When the tripod is folded together for transport, put a rubber ring around, I use an piece of an inner tyre (for cars), this is verry strong.
This is an old cinéma trick.
Get three tennisballs and cut a cross in it, large enough to put in the spikes so they will be coverd. The balls should not fall off when you lift up the tripod to move it.
We used it to put it on the ends of the light stands to.
Good luck,
Philippe