There were View-Master packets available years ago, but not anymore. Without doing a lot of homework, here is a brief overview of what is out there:
3 Reel Packets- GAF green stripe "The Wonderful World of Disney". All of this series has the WDW "Florida flag" logo. I'm guessing they started selling these in 1972 through 1975 or 76.
A 947 Main Street
A 948 Fantasyland
A 949 Adventureland
A 950 Liberty Square
A 951 Frontierland
A 952 Tomorrowland
The second series of three reel packets had the same numbers, but the GAF green stripe read "The Wonderful World of WDW (mouse world logo). The also contained a 16 page illustrated booklet. These replaced the packets mentioned above and probably sold through 1987.
A three reel packet was issued for the America On Parade theme; packet A 954.
There was also a 7 reel plastic can set that as far as I know, was only sold at the park.
After the packets were dropped, three reel blister packs were sold on hang cards. I'm not sure if these were only sold at the parks. They were copyright 1988 and sold into the early 90's in the park. I'm pretty sure there were packs from EPCOT in this series.
There is also a series of Talking View-Master Reels from WDW number AVA955. Three reels in a large flat box. These reels require a special viewer, player.
By far the easiest and cheapest way to add them to your collection is eBay. And summer is usually a great time for buying on the Bay!
Good Luck in your search!