Hopefully this will be of some help. I have seen displays of this type for artifacts in museums and what they have is a box with a shield. The normal UV lights are on. When you push a button or switch they go off (or can possibly stay on?) and the light bulbs come on, showing the difference.

You might do the same with a sliding door that means both sets of lights are always on and the slot open or blocks one type of lighting.

There are a variety of H&C markings, with various locations, colors and sizes.

Here are some that may show up as very well marked. $1 Golden Nugget, Rio, Luxor (of course), Casino Magic. $25 Caesar's Palace.

Some with cane variations, at least in my older chips, Showboat, O'Sheas $5, Four Queens (old blue table chip) Harrah's $1, Frontier. These all had small or medium H&C markings, unlike the new large size.

The best light I have found for showing these or viewing is a standard fixture with the GE F15T8-BLB Blacklight. It's 15 watts and fits in the common portable lamp fixtures meant for grow lights or small workshop lights. I have a pair for photos so I get even illumination.

As far as true protables, I found a very nice little one at a coin show, battery operated. As small as a travel alarm clock and works just fine for viewing at the casino. Of course security will be interested in whatever you are doing. ;-)