Hi, and welcome!
Hmmm...not so sure exactly when the crossover happened, but DONs may have come out in the early 70's.
What date do you get when you enter your serial here : ilovemyspeedmaster.com ?
http://speedmaster101.com/price-chart-2/
Nice speedie...WIGH
Edit : Incase you didn't know, -69 does not mean it was produced in 1969.
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