Peugeot is in business and has a website. Contact them and ask. (I'll place my guess on 1985. I didn't follow Peugeot so I do not have a model name. I owned a Reynolds 501 that was probably 4 or 5 years later and it was a fun ride! Enough so to inspire an expensive custom patterned after it. (It was hit hard by probably a SUV before I got the frame. I retired it before it failed.)
Oh, you may fall in love with this ride. If you do and want fenders that fit with decent sized tires, go to the River City Bicycles website and look at their fender brackets to solve the challenge. They work very well and you can easily make your own.
Ben