I shoot a Nikon D7100 in an Ikelite housing and I travel with it.
I'm not a fan of Pelican hard cases. While Pelican cases provide great protection (and yes, I've used 'hard' Pelicans lots in the past for photo assignments), the cases are pretty heavy. I like to keep my camera system in the cabin with me when I do airline travel.
I do have a Pelican case, but it's not the hard variety. It's a Pelican Gustofson Photo Safari soft camera roller case. I found it in a local camera shop. It was lightly used. My entire D7100/Ikelite housing, three lenses & strobe w. arms system fits in it. This particular case has a zip-off bag that my dome ports (6" & 8") fit in. The zip-off bag also rides in the cabin as a carry-on.
I've never seen another camera case like mine, but there are some that are very similar. The cases made by Thinktank are similar. I was actually shopping for a Thinktank case when I found my Pelican case.
I posted some photos of my underwater system and Pelican case system on my Cortez Blue Photography Facebook page a while back. If you do Facebook just do the 'like' Cortez Blue Photography on Facebook thing and you should be able to see what I use. It's amazing what fits in that Pelican soft case.
Of course, if you'd like more information about using a Nikon D7100/Ikelite housing system feel free to PM me. My system works great and I've produced some good work with it. You can look at my photos at www.cortezbluephotography.com.
I attach my underwater rig to my BCD with two straps. When attached to my BCD d-rings, the rig sits right in the neighborhood of my belly button. I felt it was important to be able to use both hands for something other than hanging on to my rig without losing the rig or having it dangle off me. The strap system I made makes handling the rig really easy when it enters and exits the water. If you're interested in seeing what the strap system looks like, let me know and I'll try to send you some photos.
I also pack (in regular checked luggage) a soft cooler that I use to transport the assembled rig to dive boats & sites. I put the rig in the cooler between dives. Last year, my 8" dome port got scratched on a dive boat out of La Paz when the crew dropped it into the boat's camera tank. I won't ever use a 'community' camera tank again.
Polar 24 Pack Soft Cooler works exceptionally well for me. The insulation provides padding and the shoulder strap that comes with the bag works okay for me too. I simply put my rig in the bag during surface intervals with a towel over the top of the camera rather than using the bag as a fresh water rinse tank.
After getting a dome port dinged pretty good last year in a boat rinse tank, I stopped using the boat tanks. I also have watched too many non-photographers use the boat tanks as mask rinse tanks frequently despite instructions from the boat crew not to do that.
I do use the cooler as a fresh water rinse/soak tank when I return to my hotel room... just set it in the tub or shower and fill it up (just make sure not to cover the tub/shower drain).
The Precision Dome is considerably smaller than the large 8" Ikelite dome. It is manufactured specifically for different lenses. For example, my Precision Dome for my Nikkor 10-24mm won't work with my Tokina 10-17mm. I know several underwater photographers who simply started with a macro set up rather than purchasing all of the necessary gear (lenses, ports, & extensions) to shoot macro and wide angle.
Well, not everyone favors the Tokina 10-17mm Fisheye. I've got one, but I like my Nikkor 10-24mm better with my Nikon D7100 rig. While the Tokina Fisheye undoubtedly has applications, I'm not a fan of the curvature one gets with it. Of course, tastes vary.
While I've got the large 8" dome and appropriate extensions to use with both the 10-17 Fisheye and the 10-24, I use a Precision Dome with the 10-24.
Hope your macro is a Micro Nikkor 60mm 1:2.8G ED. It's a great lens.