Go to
this page, and about 2/3rds of the way down, Sheldon posted a table of gear center-to-center spacing for almost all modern rear ends. Note that some of the Suntour 7-speed stuff had two different spacings within the same freewheel. Never going to get one of those to work properly with the Shimano Indexing System (SIS).
FWIW, Sheldonbrown.com is THE web repository for practical bike upkeep, especially for the out-of-fashion gear. Sadly, Sheldon is no longer with us, but his wisdom lives on.
The modern Shimano, and Interloc, 7-speed freewheels will index perfectly with any 7-speed SIS shifter you want to through at 'em. Mountain, down tube, bar end, or integrated, doesn't matter.
I like 9 speed too; still a standard in the MTB world, although out of favor for road applications. Cheaper and slightly heavier duty chains, 10% larger center-to-center spacing on rear cogs, which makes adjustment easier, and till recently, a fairly large supply of cheap used parts from those upgrading to the latest and greatest.
I've seen reports from some in the tandem world, that swear 9-speed is the way to go, and swear at 10-speed. I don't have any personal experience in the matter, so I don't know if the reports hold any water.
Do note, the Phils set being sold on Rivendell's site are very well thought out, albeit pricey. The flange diameters, and axle spacing, were picked to keep the same spoke length, front and rear, and drive and non-drive. Most of the wheels that I've built have required 3 spoke lengths, one for the front, one for the drive side rear, and another for the non-drive. If you are taking an extended tour, this detail would be important.