Re:
I've got something that ticks most of your boxes, only one it fails on is its immaculate. Pipedream scion 853 in 19 inch, disc only with straight 1 1/8 steerer, 27.2 seat tube. I say immaculate, it has a scuff to the 853 decal, though I have a full replacement decal set. Its in a metallic grey colour, and probably only done 200 miles around center parcs. Until recently it was a full bike, but I sold the gearing. Not desperate to sell, have replacement gearing to fit, but I need to reduce the collection as losing my garage soon and will have less storage space as a result.
If interested, let me know, I have a build thread, just search for scion in the >98 section for some pics.
Its a lovely ride, hence not that desperate to sell, but I have to make some tough calls to get down to a reasonable number of builds.