Hardware store owners and young graffiti artists beware: You may soon face a $1,000 fine and up to a year in jail for selling or buying two of the most lethal weapons threatening the city’s quality of life: spray paint and markers.

City Councilmembers Peter Vallone, Jr. and Philip Reed are pushing legislation to strengthen existing anti-graffiti laws. Decades ago, the city banned the sale of aerosol paint and permanent markers to anyone under 18 and barred vendors from putting those items in accessible display cases. Since then, one mayor after another has vowed vigilance. David Dinkins offered a $500 reward for tips on art vandals. Rudy Giuliani created a task force that encompassed 17 city agencies and offices. And in recent months, Mayor Bloomberg has stepped up efforts to enlist neighborhoods in a program to paint over graffiti.

None of that, say Vallone, Jr., and Reed, has worked. This summer City Council investigators sent minors into 70 hardware stores and seven art supplies shops to attempt illegal purchases of spray paint and markers. The results: Half the hardware vendors and all but one of the art stores were scofflaws.

And the evidence on the street is clear, says Vallone, Jr., noting that his office gets 10 to 20 complaints a week about graffiti.

So he and Reed are calling for a law that makes a second graffiti offense a class A misdemeanor. (As of now, any offense gets a $500 fine and three months in jail.) They also want to outlaw the sale of etching acid to minors, and require stores to post signs explaining the law.

For juvenile justice advocates, this push reopens an old debate. “The city shouldn’t be putting people in jail for low-level crimes like graffiti,” argues Mishi Faruqee, head of the Correctional Association of New York’s Juvenile Justice Project, noting it costs about $350 a day to imprison young offenders. “And stiffening penalties never works as a deterrent.”

Young graffiti artists have certainly found ways around it. They either have older friends buy the spray paint for them, or shop online or at underground graffiti paraphernalia shops.

“It didn’t work in 1982, it didn’t work in 1992, and it won’t work now,” scoffs Vee Bravo, a hip hop activist and former graffiti artist. “The kids are smarter than you.”

The councilmembers are also up against a budget crunch. The Department of Consumer Affairs says it’s doing the best it can with the resources it has. While agency staff would like to do more, Assistant Commissioner Pauline Toole notes that hardware and art supply stores are not licensed, which means Consumer Affairs would first have to invest in figuring out where those shops are. “It would take resources to do it,” Toole says.

Still, that financial reality doesn’t seem to bother Vallone, Jr. “It’s one of the reasons I don’t think we need to be cutting the police [budget] at all,” he says. “Even the so-called quality of life crimes need enforcement.”