They made many many more shorts besides that (there's a full list in Bill Warren's book The Evil Dead Companion), but I'd never heard about bootlegs being available of Shemp Eats The Moon and Happy Valley Kid. The latter, in particular, is kind of legendary among Raimi/Campbell fans.
Yes, just incase anyone doesn't have the book, heres the full list of shorts:
Inspector Klutz Saves The Day (1969)
Pies And Guys (1971)
Corny Casanovas (1971)
Out West (1972)
Oedipus Rex (1972)
Supa' Bad (1973)
D-Day (1973)
Day Of Violence (1973)
Son Of Hitler (1973)
For Crimin' Out Loud (1973)
A Night In The Sanitarium (1973)
Three Smart Saps (1973)
Loose Loot (1973)
Piece Of Mind (1973)
Booby Bartenders (1974)
Three On A Couch (1974)
Three Pests In A Mess (1974)
Half-Wits' Holiday (1974)
Manhunt (1974)
Curse Of The Werewolf (1974)
All The Worlds A Stooge (1974)
No Dough Boys (1974)
The Singing Nuts (1974)
I'll Never Heil Again (1975)
The Great Bogus Monkey Pignuts Swindle (1975)
The James Hoffa Story (1975)
The James R. Hoffa Story, Part II (aka Home Sweet Homicide) (1976)
James Bombed In Here Today, Gun Tomorrow (1976)
Attack Of The Pillsbury Doughboy (1976)
Uncivil War Birds (1976)
Myster No Mystery (1976)
Topanga Pearl (1976)
Picnic (1977)
Charlie's Angels (1977)
The Kids' Film (1977)
Six Months To Live (1977)
The Happy Valley Kid (1977)
Lonely Are The Brave (aka The Drama Movie) (1977)
Civil War Part II (1977)
Final Round (1977)
Acting And Reacting (1978)
Holding It (1978)
Shemp Eats The Moon (1978)
It's Murder (1978)
William Shakespeare - The Movie (1979)
Attack Of The Helping Hand (1979)
Clockwork (1979)
Night Crew (1979)
Within The Woods (1979)
Spring Cleaning (1979)
Fish Sticks (1979)
The Blind Waiter (1980)
Stryker's War (1980)
Toro Toro Toro (1981)
Cleveland Smith Bounty Hunter (1982)
The Sappy Sap (1985)