Our Company recently designed and manufactured new type of build plate to upgrade popular Prusa i3 variations from various sources. This plate works with silicone heater, for fastest heat up, or can be used with MK1/MK2/A/B types of PCB heaters. 3-point level adjustment is possible with this plate, when you use it with silicone heater. Plate is GPL open source design, it is published on the thingiverse.com
Plate is available as a short kit, full kit (whit heater), and complete upgrade kit, together with aluminium Y carriage plate.