Bike friday uses aluminum chainguards, so has them FS.
My IGH bike, I have a 130bcd crankset 53t chainring + a disc chainguard
where an outer chainring would be.

there are 3 on one chainring bolt, sets, to make the 2 chainring + chainguard setups you desire.

built up a wide step double decades ago, 52, 36t + a chainguard in 144bcd,
Campag & Gippiemme, (gpm) parts ..

all sorts of interesting combinations can be made up, with a bit of ingenuity
Even if not already sold .. as is