The last hurrah for such a source is unopened product. With each cello pack, vending box or case that is opened, there are hopes and dreams of mint or gem mint gradeable cards inside, which are bringing a premium on the secondary market.
A hurdle to overcome is finding sources for unopened product. Collect Auctions is offering more than 50 different unopened lots in its latest catalog sale, which opened Monday and continues through April 2.
Topping the list is an unopened vending case of 1975 Topps Baseball, one of the most sought-after sets from the 1970s. Bidding opened at $10,000. In December 2013, Collect sold a 1975 Topps cello pack case for $66,569.79.
Another 
gem is a 1970-71 Topps Basketball 2nd Series vending box (packed that season inside a display box).
While some may choose to leave them unopened as an investment or simply part of an advanced unopened vintage collection, others may have designs on opening up a sort of sports card time capsule.
“Every collector dreams of cracking open a box of old product, but how often do you get that chance?” said Steve Bloedow, director of Collect Auctions. “In this sale, we provide multiple opportunities to experience that joy.”
The other top draws in the unopened category include the following vending boxes: 1968 Topps Baseball 7th Series, 1970 Topps Baseball 4th Series, 1970 Topps Baseball 5th Series, 1971 Topps Baseball 3rd Series, 1972 Topps Baseball 3rd Series, 1970-72 Topps Football Series 1, 1971-72 Topps 
Basketball, 1980-81 Topps Basketball, 1968-69 Topps Hockey, 1971-72 Topps Hockey and 1975-78 Topps Baseball.
Speaking of vintage cards in their original state, Collect Auctions will also offer Post Cereal box backs filled with cards – not cut out like what is usually found in the market. The auction will feature group lots of uncut Post Cereal panels from 1961-63 baseball and 1962 football.
Another staple of Collect Auctions is signed card sets. This auction will feature a 1975 Topps baseball near set (640/660) and 1985 Topps Baseball signed near-complete set (788/792).
More autograph highlights include a Mickey Mantle and Roger Maris signed 8-by-10 photo (PSA/DNA 9) and a Roberto Clemente signed 1959 Topps card. Yankee fans will also have the chance to chase a 1978 Yankees team-signed photo and index card display that includes Thurman Munson, along with tickets to Games 1-6 from the 1978 World Series. There is also a Derek Jeter signed 25-by-31-inch lithograph hand-numbered limited-edition (5-of-22) signed by the artist, Adam Port.
Game-used memorabilia highlights include a Robin Yount 1991-93 game-used and signed Louisville Slugger bat (graded MEARS A8) and a Carl Yastrzemski 1978-79 game-used Louisville Slugger bat (graded MEARS A8). Game-used bats from Joe Mauer (2009, MVP year), Joe Morgan (1981-83), Kirby Puckett (1993 All-Star Game) and Rod Carew (1983-85) are also available.
A Bobby Thomson 1955 game-used Milwaukee Braves home flannel jersey leads the game-used jersey portion of the sale. Thompson, the hero of the 1951 playoff against the Brooklyn Dodgers, moved on to 
Milwaukee. His broken ankle in the spring of 1954 paved the way for 20-year-old Hank Aaron to make his mark.
There is a scarce Harry Hooper single-signed MacGregor baseball, a Rogers Hornsby signed 3-by-5 index card and black-and-white Hall of Fame postcards signed by Larry Lajoie and Mel Ott.
High-profile signatures in the non-sports world include Aaron Burr signed bank check (1800), William Fargo signed original stock certificate (1868) and Mahatma Gandhi signed House of Commons card (dated Sept. 16, 1931).
For more information on this auction, visit http://www.collectauctions.comor call (888) 463-3063.
Related Stories:
Vintage Topps Shipping Cases a Unique NSCC Attraction
Why Baseball Cards Came Out a Tad Later in 1964
Huge Roster of Vintage Unopened Boxes, Packs Heading to Auction
Heritage Auction Includes Dozens of Vintage Unopened Boxes
Boyhood Heroes and Autograph Books: The Day That Gave Birth to Paul Hornung’s 1962 Post Cereal Card
MJ, Griffey Debut Tickets, Vintage Cards Among Heritage Lots
The Brick is Back: 8 1952 Topps Pack Lot, Other Vintage Unopened Up for Auction
Vintage Packs, Key Rookies, Rare Photos Join T206 Wagner in MHCC Catalog
