This was always a pet peeve of mine, but the old KIT never had a medicine cabinet in the bathroom. There was certainly space for one, but there was never any sign that one had been installed.
Every other camper I looked at before I bought the old girl had a medicine cabinet, but for some reason, the KIT didn't.
At first, I tried looking up what brand and make of cabinet was commonly used in most RVs and discovered that it was just a basic Zenith plastic medicine cabinet. However, they had access to a spring loaded tab that was installed underneath the cabinet to hold the door shut during transit, in addition to the already existent magnet latch.
I searched high and low for a solution, but in the end, I wound up buying this:
Zenith Metal® Stainless Steel Swing Door Cabinet (X311)
I found it at Lowes for $12. The irony was that the Lowes website listed all the stores in my area as not carrying it. However, I found a great big pile of them waiting to be sold at discount right at my nearby store.
I wound up installing my flipped over the other direction so that it swung into the bathroom when opened instead of opening right in my way when trying to reach into the cabinet from outside the bathroom.
So, now my bathroom has a nice medicine cabinet and now I don't have to dig through a bag every time I need my toothpaste or pepto bismol.