Some prices
Overhead projectors of 250 watt cost approximately £ 250 (£110) but these are less used these days for obvious reasons. A powerful OHP of 400 watts with much brighter colours and sharper definition is much more productive and costs about £ 320. New lamps cost £ 6 and £ 9 respectively.

TTE offers sturdy 400 watt projectors
TTE-Visual projector(s) HP1400 400 Watt Chinese made, enhanced with European parts, EU certified, strong new generation 3-lenser, lamp changer (plus 3 spare lamps included) @ E 279
(10-19 units, net per unit @ E 259 / 20-49: @ E 239 / 50+: please contact us) 
Wictor-projector(s) 400 Watt Swedish-German made extra strong, 3-lenser, lamp changer (plus 3 spare lamps included) @ E 359   (10-19 units, net per unit @ E 339 / 20-49: @ E 319 / 50+: please contact us)