A pic would help but it sounds like you have a Japanese built 15 class clone. These were most common from the late 1940s to the late 1950s but that's about as much info as anyone can give you. They're great machines, a well tuned clone will generally sew a bumper to a Buick with no hesitation. No, they don't have that smooth feel of a 201-2, nothing else does, but a clone will sew what a 201 won't.
Cari