Ford Dizzy Parts: where to get them?

[Midlife]

I have a Motorcraft service replacement distributor, and the centrifugal timing comes in very late.  I can easily run 16* advance at idle, and have only 26* total timing at 2500 rpm (as high as I could maintain the revs with the curb idle screw).  I'm sure I'm missing a fair amount of performance.

Where can I get a set of springs and weights to play around with?  NPD doesn't list them in their catalog.

[Starfury]

A lot of auto parts stores have a cheapo performance rack that will include a distributor advance rebuild set, including several springs, bushings, and sometimes even weights.  I know we've got one here at Napa.