The Easydive housings sound great but there are some issues you need to consider, for example the housing is way bigger than it needs to be and the viewfinder and port centrelines are fixed, so when you line up one the other doesn't line up. You also need to check which features are available to be used - not everything is programmed to allow you to control it in the housing Here's an old post about it:
View archived post in: Easy Dive Housings - Any Good?
On the question of the dome, a 160dome is too small for a 14mm lens, the corners will be pretty poor. Most systems recommend a 230mm dome to use with a 14mm lens on full frame.
I would also suggest that just because you have a camera on land and like using it, doesn't necessarily mean it's the best choice to put in a housing. Put it another way, the camera is the not the first to consider - rather it is a total system approach - what will it cost to buy all the domes and lenses you need to use with your system. Full frame systems are generally more expensive, they need bigger domes with with rectilinear lenses, the housings , at least for aluminium housings are significantly more expensive and for wide angle work tend to be more demanding of strobes as you need to shoot the lenses well stopped down behind domes. Water contact optics are another option to consider and they will work well with certain Sony lenses but not every housing system will have suitable ports to use with the wet lenses. I would suggest working out which types of lenses you might like to use and work backwards from there.
A 230mm dome is really big for transport and the easydive housings are also reported to be big and heavy and won't be easy to transport if travelling by air. Fisheye lenses at wet optics can be much more compact for travel.
