Crane Cams 1.275" Dual Valve Springs, Good to .650" Lift. Have 3000 miles on them. PN# 40-144832-16. Here is some info found in the Cam sticky from the internal section.
A dual spring setup rated for up to .650 lift. When buying duals you’ll need the dual springs (obviously), titanium retainers, new dual spring seats, and new valve stem seals.

Outer Diameter Outer Spring 1.275
Outer Diameter Inner Spring .937
Inner Diameter Inner Spring .667
Damper No
Seat Pressure @ Installed Height 112 lbs @ 1.800
Open Pressure and Height 352 @ 1.150
Coil Bind 1.045
Maximum Net Lift w/.060" Clearance .650
Average Spring Rate (lbs./in.) 352
Just the springs. $95 shipped. Paypal addy is Sweetss@cfl.rr.com