I think 500 X magnification is to high. A binocular microscope (or stereo microscope) with 10 - 20 X magnification, you will be able to sex any exuvium. A light microscope where light has to penetrate the subject from the bottom (like in slides) is not ideal because the lens would normally be very close to the slide making it difficult, if not impossible to manipulate the exuvium...
If you want to go digital, Celestron makes a little "hand held" USB microscope.
The magnification is good, it has 10 X - 150 X digital zoom. You install the software to your PC, then view your subject on your PC monitor. I find it difficult to work with because of this, but that is an age thing and not the microscope. It is a bit like playing a 3D PC game because left can be right and top can be bottom. This confuses me to no end, but can be overcome by rotating the microscope.
It is very light sensitive. It has 6 little LED lights built in and illuminates the subject sufficiently. What I found useful is the fact that an image can be taken with this microscope by pushing a button on the device or with a click on your PC mouse, which is then saved to a folder on your PC. It also has video capabilities which I found a bit useless because if the subject farts, it's out of focus. I does not have auto focus.
A good little tool in general and at R700 or so, not bad value. It is personal preference I guess, but I prefer my 15 year old 10 X stereo microscope.
This was taken with the Celestron, I believe good enough for sexing Tarantulas ??