I take it there's no identification on the connector.
It looks a lot like a locking Berg, but which one out of thousands would be tricky.
A 2 second check on Crutchfield didn't yield a replacement, but they used to be the most helpful resource in the business if you call them.
Another place to try would be local auto audio installers.
I can't read the ident under the DaimlerChrysler, but you may want to try Googling on boston acoustics, daimlerchrysler, and that big number.
Do the new speakers have the same connector on the speaker?
If so, that would increase the odds a local car audio store would have something that would fit.