Dura Ace high flange / Aerohead wheelset

Track use only when I bought them, I used them for a few months on the road over the summer and rebuilt them to new rims. Been sitting in my kitchen ever since. They spin freely and the one I overhauled had lovely shiny cups and cones with no pitting and minimal wear.

Will these take a freewheel cog and can they be used in 126 spacing with some whatever-you-call-'ems?