Tandell offers rigid carbon forks, in both 27.5+, the TD-MF01:
http://www.tandellbikes.com/mtb-275-carbon-rigid-forks_p0930.htmlwhich has a 515mm axle-to-crown with 49mm offset.
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A 29+ fork not on the website has a 531mm a-c and 49mm offset:
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Both are intriguing as suspension-corrected rigid forks for plus-sized frames. The 27.5+ fork might even work for 29+. But both have a slightly shorter offset than the more common 51mm (not sure just how different that might feel). Even more intriguing is the possibility of another frame(s) coming. They have the forks, I hope they get frames soon. Daniel from Tandell answered emails quickly, and he posts on mtbr sometimes.
Does anyone here have any experience with these forks?