The collective hive on this forum is pretty good at figuring out the dates on older bike gear. The condition of this part along with it being incomplete will make that hard.

Lyotard is a common French brand. This website has pictures of Lyotard pedals and often the dates of production,

https://velobase.com/ViewBrand.aspx?...8-9eb411201d39

It's not yet April 1 so I assume this is a serious inquiry!