Let’s talk about some rare track.
The 3015 12” Radius 1/8 Circle was part of the 1981 initial release and was available all the way through 1985.
It was sold retail as the 3708 with two track pieces per card. The best I can tell, it used a 95-2-009 card, although I’ve never seen a 3708 sealed. It uses Tyco’s B5844 item number, as it’s based off the much more available black track.
From what I can tell, this track could only be “special ordered” or bought from the mail order sheet.
Tyco made Assortments every year that contained a variety of items. These can be found in the yearly Catalogs released for retailers.
The track Assortments were numbered 3000 (‘81/‘82), 3001 (‘83), and 3002 (‘84/‘85). The 3015/3708 was not included in any assortment, and was never in a set. How these were acquired I’m not real sure, other than what I said about mail order, or a retailer having to directly order from Tyco.
Personally, it took me a loooooong time to finally acquire this track. I was fortunate to find four first gens with lines. I began actively searching for these for a while before finally scoring those.
Of course, after I finally saw and bought them, a few popped up, but now it has been a long time since I’ve seen them again.
I’d say the most desired track is the 3017/3727 Rail Crossing, as I’ve hardly seen these sell for under $75 each. I did have a chance to get a sealed first gen but I let it slip away, and I’ve regretted it since. But even still these pop up fairly regularly, and usually sell fast, even with the highly inflated pricing.
IMO, these 3015’s are the single most obscure and rare track parts.