My rotator cuff surgery last year was 6 weeks in a sling, sitting sitting up, then 9 months of PT and exercising to begin to feel OK. Now at 14 months post surgery, full range of motion but still working on strength. I went diving, gently, at 4 months post-surgery, and had problems getting up the ladder to the boat, and had to hand up my camera with my good arm.I made it the way I did so I could collapse it and clip it to my harness/BC. When I get really old I'll make a PVC walker - lol. Not sure how to make that collapsable. Might have to bring it with me and leave it as an indicator of the exit point. At least I have a lot of time to think about it and get it designed.
I'll let you know how it works once I get a chance to use it. May 3rd I'm having rotator cuff surgery and that's got me in a sling for 6 weeks and nothing strenuous for 4-6- months - well that's what the Doc says. I'm thinking more like 4 weeks in a sling and 2-3 months before I can dive again.
Good luck.
By the way, although the written rules do not expressly prohibit them, things like muck sticks, pointers, and walking sticks also appear (from reports on various forums and from signs at Bonaire dive shops) to be prohibited. So I'd keep its use discreet.