Hi, Nice Iverson. I would guess early '70's because of the pedal reflectors and the BMA-6 decal on the seat tube. I don't think the saddle is original. Many years ago I owned a new old stock example in orange, and it had a cheap, very shiny black saddle with silver stripes screened on the surface. I do believe the tires are original to the bike. Outside of the weld repair, you have a really clean example. It was an inexpensive bike and not many survived. Nice find!