You can get the Perspex people to cut it to size for you..

then attach it with screws with decorative tops?

we had to get Perspex cut to size quite a few times so we know that service exist.

where are you ?

google Perspex cut to size ..then name of city ?

Perspex or acrylic will scratch alot easier than glass, so you'll need to treat the top with care. But a toughened glass top would be quite costly

I'd get toughened glass.

Google "glass shops in Wagga Wagga". Nice place, I've been there:

click on it

No worries.

I am not an expert in this field either but I think you are onto an excellent idea - it will look fantastic - you may be even be able to get a coloured surface. I would call your local glass provider if they can not help I am sure they can refer you to someone who can. Also send them a photo.