I replaced the foam on my Bose speakers several years ago with help from Simply Speakers in Florida. They were very helpful and prompt. My neighbor was so impressed with the sound he did the same for his Advent speakers.
I refoamed the woofers on my Advent Legacy pair nine years ago, SimplySpeakers was the kit source. First attempt, one cone got a tad misaligned and rattled so I ended up replacing both woofers, SpeakerEx was the source for that.