This doesn't really help, but here are some ended tracks on ebay.
https://www.ebay.com/sch/i.html?_odkw=e+...ck&_sacat=0

Both styles are in these completed auctions. One style said 70, while the other is grouped 70-74. I personally never knew that there were 2 different styles of tracks, but I'm not a huge E body guy either.
Matt