Kato Unitrack availability can look random from the outside. Some items genuinely disappear. Many more just go quiet for a year or two, then come back.Sometimes these have new numbers and sometime not!

Here are the real problem children:

• 20-840 Double Track Viaduct Set — discontinued as a set, replaced by 20-872.
  What to do: buy the newer set, or build the viaduct from individual viaduct pieces and piers.
• 20-070/20-071 - not available separately but short straights are available as part of the 20-091 or 20-092 packs
• 20-652 Automatic Crossing Gates (single Track) or 20-652-1 North American Style Automatic Level Crossing. (or 20-650) Sadly no alternative for this is currently available except for the 'manual' 20-027 Level Crossing Track.
• 20-011 and 20-022 plate track - no longer available, please use normal track instead.
• 20-021 Ground Level Road Crossing Track - no longer available - use 20-027 Level Crossing Track and 20-026 Rerailing Track 124mm (2).

If you’ve got a plan that specifies an awkward part, we can usually get you to the same end result — but sometimes the answer is “change the plan”, not “hunt eBay at midnight”. Let us know if we can help.