This is just a really rough categorization of the standard passive production humbuckers, but would it be accurate? The pickups weren't necessarily introduced in the order that they are in, within each category, necessarily....
* Mid-70's through early 80's
SH-1n, SH-1b - The '59
SH-2n, SH-2b - The Jazz (made for Jeff Beck)
SH-3 - The Mag (later modified into the SH-3 Stag Mag)
SH-4 - The JB Model (made for Jeff Beck)
SH-5 - Duncan Custom
SH-6 - Duncan Distortion (later SH-6b Duncan Distortion bridge)
SH-7 - Seymourizer II (later SH-6n Duncan Distortion neck)
* Mid-80's through early 90's
APH-1n, APH-1b - Alnico II Pro
SH-PG1n, SH-PG1b - Pearly Gates (made for Billy Gibbons)
SH-8n, SH-8b - The Invader
SH-9n, SH-9b - Silverbird (made for Gibson)
SH-10n, SH-10b - Full Shred (made for the Kramer Nightswan)
SH-11 - Custom Custom (made for EVH)
SH-12 - Screamin' Demon (made for George Lynch)
* Mid-90's to Present
SH-55n, SH-55b - Seth Lover Model
SH-13 - Dimebucker (made for Dimebag Darrell)
SH-14 - Custom 5 (made by the forum)
SH-15 - Alternative 8
I'm really curious about the actual years of introduction for each pickup, though....