Memorabilia collecting is not a hobby for getting rich. Still, nobody says you shouldn't hold onto stuff that might someday be worth a dollar or two. s

As Presidential 1980 heats up, here are a few pointers on the kind of political buttons and other memorabilia most likely to increase in value:

Any button or item that is produced or sanctioned by the candidate's political party. Since 1969, many items have been produced simply for collectors. These are little more than souvenirs.

An authentic, limit-edition political button usually will have a legend on its edge like, "Paid for by Carter for President Committee, Robert Lipshutz, Treas."

One of the reasons that a genuine McGovern-Eagleton button is so rare is tht immediately after Sen. Thomas Eagleton was dropped from the ticket, the Democratic Party abruptly canceled its order with Manhattan's N.G. Slater.

(Knowing there would be a tremendous demand for the buttons, Mat Slater printed up thousands on his own. They sold well, but will never match the real thing for historical or monetary value. Slater also notes that the law now requires that such reproductions be marked clearly.

Buttons with a portrait or likeness of the candidate or candidates. This is a throwback to the time, before mass-circulation newspapers and television, when political buttons and posters showed people what the candidates actually looked like. A button with such a likeness is still valued more than one simply bearing the candidate's name.

A button bearing a slogan unique to the period or the political campaign. During FDR's time, this would have included the "No Third Term" and, later, "No Fourth Term" buttons worn by his opponents.

Later slogans include ones like "I Like Ike" or "Nixon's the One." A button with both a picture and a slogan is probably worth holding onto.

A Franklin D.Roosevelt button with FDR's likeness and the slogan, "Carry on With Roosevelt" recently went for $3. An Alf Landon button that said simply "Landon-Knox" (Frank Knox was the running mate) sold for $1.25.

"Theme" or "cause" buttons. A favorite of collectors, for example, are anti-Vietnam War buttons, such as one saying "Enough," featuring a stark drawing by Jules Feiffer.

Theme buttons show how ideas and designs have been repeated over the years. You think Carter's teeth were unique as a political vehicle? Guess again. Buttons featuring Teedy Roosevelt's toothy grin were very popular years back.

Any button commemorating a single event. But the importance of the event dictates the value of the button.

A button that could be valuable is the one produced in 1976 for the Republican convention, showing Gerald Ford and Ronald Reagan in cowboy getups. The button commemorates the "shoot-out in Kansas City" (site of the GOP convention) in which Ford bested Reagan.

Press credentials and campaign staff credentials. Candidates used to require that the traveling press corps wear buttons with things like "Rockefeller Press '68," "Richard Nixon Presidential Campaign Tour" or "McGovern Press" for easy identification and quick access to press buses and crowded appearances.

Whether by accident or design, however, the "credentials" often appeared awkwardly like campaign buttons. The assassination of Bobby Kennedy and other campaign violence put an end to all that, and the Secret Service took over credential procedure. Now the average presidential press credential is a nondescript paper badge, changed frequently for security purposes.

What is likely to be the most sought-after button or item of the 1980 campaign? It's too early to tell, but the Smithsonian's Herb Collins is losing no time in grabbing up everything he can from the GOP candidates' debate in Iowa.

"So far, it (the debate)," says Collins, "has been the most unique thing of the 1980 campaign. The first time that presidential candidates of one party have gotten together for a nationally televised debate."

Collins' previous acquisitive instincts were sound. Long ago he began putting together a collection of Watergate memorabilia (Judge Sirica's robes, Leon Jaworski's pens, etc.). The stuff, he says, is salted away for a Watergate exhibit "100 years from now."