Any chance you're wondering about a Saeco top punch? Saeco is/was a manufacturer of bullet moulds, sizing dies & the like. Along with Lyman & RCBS, they marketed lubricating/sizing machines for cast bullets. Each of the three manufactured top punches for their machines (& not coincidentally, the other 2) that were an AA fit to the nose of each of the projectiles that they sold moulds for. The top punch is the shiny dohicky you can see just under the round medallion on the green sizer down the page: http://paubeaa024.blog.com/2011/08/25/saeco-bullet-mold-chart/
I recall that one of the big three bought them out.
Just had a well duh moment. I had not considered the spelling of Sako to be used for Saeco. I am at this very moment within sight of a Saeco Lubri-sizer for cast bullets, a very well made tool.