Other aspect of the projector project

Hello everybody !
I've read all about the projector project in the articles and on the forum, and I've got one question for the managers and for the people who made it...
In the article was written that there were OH projectors for sale for 50 $ . My first question : where can you find some of these, cause I could'nt.
Second question : how much did you pay for your liesegang , cause I only found it for 180 $ ?
Third question : where can we actually buy oh projectors (I've been searching but I've only got few sites and pretty expensive)
-Last question : are the projector bulbs a standard ? Cause in the article was written that you could put a 400 W lamp in a 250 W projector, and on all internet sites, they don't seem to attribute precisely lamps to their projectors ... and I would like to know how I'll be doing to buy spare bulbs...

Thank you
Read you soon


vic