If the only thing that you put on the linkage arms is a transport box just get a piece of flat bar, say 2" wide, 1/4" thick, and drill two holes the same size as the stabiliser pins, one at each end.
You can put a bit of crank on each end. This will need a bit of trial and error and won't be adjustable but if you've got the box central on the linkage when you do the measuring it will be a cheap and better alternative to using a top link. The early T20s, 35s, and 135s used this method.