No. The 29K 171, 172, 173 series followed the 29K71, 72, 73 series. It was the last series made at the Kilbowie plant in Scotland. Is yours gray or kind of a slate blue in color?
For some reason, people have more trouble with the 171,172,173 series. Many consider the 29K71,72,73 series the best Singers every made in a shoepatchers. It is the one most copied by Clone makers in China.