Hello professor,
JFYI: Strida 1 didn’t have foldable handlebars… 
MK1 professional restore? (steering)
…for an actual Strida, to relocate the handlebar, you will need to untighten the clamp bolt (part. nr. 262) first.
Then the clamp can be opened (more) and the handlebar unmounted completely.
Now it should be possible to identify the location of the grooves (for the brass bolt p. nr 21-14-1).
After that it will be more easy to remount the handlebar;
both ends of the brass bolt (or pin) should have equal distance from the (imagined) axis of the handlebar.
(Part nrs can be found at the drawings of the Strida manual below page 11)
Please read also here:
Folding handlebars loose when lever is tightened-Right only
Did you have the problem of loose, shaky handle bars before (while locking lever 215-06 in locked position)?