Whole thing: Similar to Joerg's wooden version. (See what you started, Joerg! Thanks!)
Sliding wooden box, latched with that bent bolt. As box is slid forward, bolt pops into a notch. Shown unlatched here.
Top View, shows pseudo-side-pistol-grip to stop rearward movement of sliding box.
Large surgical tubing, folded to grip the forks and keep the snare knots in place.
Sliding box latch now down, visual latch arrangement. Pull up on bent part to release latch.
Tubes: I dunno, got these as "samples" from the local physical therapy location.
Box has about 10 long screws holding top to bottom, do not want it coming apart (and back at me).