Any boost/flyback controller that operates over that range will do. SEPIC is the same dynamics as buck-boost, specifically.
If you need a reasonably solid output current limit, you may want to add a secondary current sense / error amp and feed it back to the first error amp. Since, the built in current limit (which is typically peak current mode, plus slope compensation so it's kind of sloppy to begin with) has to be set for the minimum input voltage (maximum input current), it can deliver a shitton more output current at full input voltage.
Just last week I did one with TPS40210, 8-40V input and 12V output. The startup voltage on this one isn't quite low enough so you'll have to keep shopping around.
If you want the controller, with switch, and any other extras, to be near the footprint of a SOT-23, you're going to need CSPs, full stop.
Tim