Takeshi, who had always wanted a vintage Gretsch, says he bought Bachman’s guitar in 2014 for around 850,000 yen (US$6,300).
Long alerted Bachman to his discovery, and the musicians arranged to meet in Tokyo to swap Bachman’s original guitar with another of the same type, also made in 1957.
On Friday, at an event held on Canada Day, the pair shared a big hug and then jammed together.
They performed songs including American Woman, the 1970 hit later covered by US singer Lenny Kravitz, and Takin’ Care of Business by Bachman’s other band, Bachman-Turner Overdrive.
Bachman is not the only rock star to be reunited with a long-lost guitar: last year, Led Zeppelin’s Jimmy Page also tracked one down that went missing at an airport decades ago.
But Bachman, who had given up ever finding the guitar after four decades of searching, said he had been touched by Long’s “random act of kindness”.
“When I was playing it, I looked down and figured – time has stood still, or 50 years has just flown by really fast,” he said.
“I couldn’t have written this if I wrote it as a script. Nobody would believe it. But it’s true. It’s really great.”