As promised here is the link for sliding door tracks. It is avail thru outwater plastics..most of the time you need to purchase a specified quanity of the material but here ya go.. http://www.outwatercatalogs.com/outwate ... catalog=ow
If your looking at tracking for 1/4 inch doors I have quite a bit of excess from my last order..keep in mind that the gap between the sliding door are around 3/16 which is large enough for thumbs to excape. They do work nicely for large vivariums containing larger darts such as tincs. If you need more info drop me a not and I will share my trial and errors.
Happy new year Dan