What kind of driver could it be replaced with? Mine’s elsewhere at the moment, so can’t really check. 
Imagine any driver that takes an e-switch (eg, SP10?) might do it? “Standard” 17mm?
I don’t like resistor-type “regulation”… would be nice to have something more consistent.
Also, the “glue” that holds the mcpcb… hard like epoxy, or rubbery Fujik-like stuff? If the bezel could hold some TIRs in place, a pair of regular mcpcbs can be “floated” on the shelf with regular thermal goop (eg, AS5) once it’s cleaned.