Yw. Tbh i dont think any ti finish ive seeen will be a match to that frame. It could still look great but it will be hard to find a good matching tone.. Brushed will be brighter for sure even if its been left unbuffed for awhile. Id still think thats your best bet tho.
Your frame seem to have more of a brown/yellow tone vs titaniums greyish tone in various degrees. Perhaps thats just a photo illusion tho.
Hmm, that is a shame. The old Brompton Titanium posts had a blueish hue to them:
http://www.evanscycles.com/products/brompton/ti-standard-length-seat-pillar-ec007271
http://kleinanzeigen.ebay.de/anzeigen/s-anzeige/brompton-titan-titanium-sattelstuetze-seatpost/79629561-217-3124
This looks like a good picture to show the difference (this pic is actually on page 3 of this thread) (just about to send the owner a PM):
http://www.flickr.com/photos/tomcutting/5260606012/
This is the closest I have seen to what I need without getting one custom made, but the colour is just wrong:
http://www.ebay.co.uk/itm/Titanium-Brompton-Seatpost-Extended-Length-/280984083155?pt=Cycling_Parts_Accessories&hash=item416bf4dad3