The Star Wars Trilogy Special Edition Audio/Visual Press kit (AKA Electronic Press Kit) was released in 1997. If you have it on Umatic tape then that's probably the best quality version this forum has seen.
A past preservation of the SWTSE:EPK was babyhum's 009:
http://originaltrilogy.com/forum/topic.cfm/The-Official-babyhum-Release-Thread/post/203103/#TopicPost203103
Here's a list of the content from the ESB/ROTJ package:
Star Wars Special Edition : Electronic Press Kit
Empire Strikes Back and Return of the Jedi Electronic Press Kit
Empire/Jedi Trailer #1 Ch.1 D/M/E Ch.2 Narr. 2:00
Empire/Jedi Trailer #2 Ch.1 D/E Ch.2 Music 2:00
Featurette with text Ch.1 D/M/E Ch.2 Narr. 9:49
Featurette without text Ch.1 D/E Ch.2 Music 9:49
Font Information Slate
Chyron in order of appearance
:46 George Lucas - "Star Wars" Creator
2:02 Carrie Fisher - "Princess Leia"
2:37 Harrison Ford - "Han Solo"
2:50 Mark Hamill - "Luke Skywalker"
Empire Film Clips
"Scoundrel" 1:22
"I'll Give it a Try" 1:55
"Snow Battle" 1:31
"Asteroid Field" 1:11
"Cloud City" 2:05
"Let's Make a deal" :53
"Carbon Freeze" 1:38
"Obi-Wan Never Told You" 1:25
Jedi Film Clips
"Defeating Jabba the Hutt 1:32
"Escape" 1:46
"Speeder Bike Chase" 1:15
"Jedi Rocks" :40
Selected Sound Bites
George Lucas - "Star Wars" Creator
...on 20th anniversary of "Star Wars" :08
...on re-releasing the Trilogy :13
...on "Star Wars" as modern myth :11
...on combining serials and myths :14
...on re-compositing "Empire" snow battle :50
...on re-doing "Empire" Cloud City :55
...on Jabba music in "Jedi" :24
...on Sy Snootles limitations :38
Harrison Ford - "Han Solo"
...on reading with hundreds of actors :08
...on testing others for "Han Solo" part :08
...on first day on Millennium Falcon :06
...on flying Millennium Falcon :39
Mark Hamill - "Luke Skywalker"
...on hearing about "Star Wars" :10
...on reading with Harrison Ford :10
...on getting "Luke Skywalker" part :09
...on "Empire's" darker themes :16
Carrie Fisher - "Princess Leia"
...on first reading "Star Wars" script :16
...on preparing for "Jedi" :13
How'd you come across what you've got?