Yep. I'd say the early 70's too. I started skiing in the 80's and we didn't have the straps, just the break away bindings. I used to ski with this older guy who skied during the 70's and he appreciated not having those old straps because if he fell and started rolling down the hill, his old skis would just follow him down, whacking him on the back of his head all the way down.
I agree that you wouldn't get much for those now. And I used to have a ton of neon colored clothes for skiing. I miss my bright pink fanny pack.