Excellent build!
I think I can recognize the flashlight, and I'll take your word on the scuba regulator parts, but I'm assuming the walkway, railings and ladder are from another source. Are they lasercut MDF and/or card mayhaps? On the other hand; they're too thin for that, so perhaps granny-grating and plastic strips?
No matter what though; the overall effect is spot on; Starwarsy level 9!