Here is a small pile of TD and TF gearbox parts related to the reverse gear.  There is the gear itself, the shaft it slides on, the lever that moves the fork (with its pivot bolt and nut), the fork, the fork shaft and the lock bolts that secure the two shafts in the housing.  The bushing pressed into the main gear looks fine, with easy movement but no slop.  All the parts have been bead blasted and are ready to use.  Only the gear ($250 from Moss Motors) and the fork shaft ($29) appear to be available.  That means it's a good time to stock up on some good used spares.

Be sure to look at my other gearbox items.