Ti Spring for Vivid
I very much doubt you'll find a used Ti spring to fit the Vivid. You'll need a spring with a 1.5" ID as you're probably aware.
I'm aware of only three Ti spring manufacturers who offer 1.5" ID springs.
RCS have made some 1.5" ID springs for Avalanche, but RCS didn't have any in stock when I asked them a couple of months back.
Obtainium Performance Products look like they make nice 1.5" ID springs, but I emailed them and never got a reply. hmm
Diverse Suspension Products make 1.5" springs and told me they have a lifetime guarantee against breakage and spring rate! They were super helpful too! DSP said their 1.5" ID springs are only made in limited production runs so I have one reserved for their next batch.