A friend of mine pointed out this website to me.
http://www.doubleslitexperiment.com/
The site posts an interesting theory; I'll take a quote from the sites document:
"For some unknown reason that haunts scientists, everything we perceive as having mass is just a wave of information (or...
I found this link for you, but I'm not sure if it really helps.
It shows the equipment your are looking, but no prices are listed.
You may be able to get the build specifications from them if you ask.
That way you can to build your own...