I was out last night and spotted a Peugeot locked up as I passed. At first I was thinking it was your typical 501 bike with Maroon paint and a chrome fork, But this one had Mafac cantilevers. Any idea on what model it was?

That's not enough of a description to identify anything. You need to post a picture or a lot more detail in writing.

What more do we need? How many Pugs came with MAFAC cantis and maroon paint?

it is an '85 Marseilles Grande Touring Special.

"Today I passed you on the street
and my heart fell at your feet
I can't help you with your Peugeot ID"

It was probably the elusive PCX-10, the short lived, high-performance cyclocross bike.