[vcf-midatlantic] Anachronism! Commodore 64 in 1975!

My vintage computer nerdiness kicking in. I was watching DC Legends Of Tomorrow Season 1 Episode 3 at 9:34. And they are in 1975. Rip Hunter is breaking in the bank's computers so my nerdy-sense kicks in to see which kind of computer they using in 1975. The monitor they are using is a Commodore 1802 monitor and which computer is Rip Hunter typing on? A commodore 64! And as we all know it debuted in 1982. So this show has an anachronism! Guess Commodore 64s are fairly easy to obtain as opposed to finding something authentic for 1975.