As long as it doesn't need more than 2 separate output channels, it should be fairly simple to make one that is less than 20x20x10mm. It'd likely have an output of 5 to 8A at well over 36v depending on what suitable components are available, so that should be ok to drive 2 Burkets in parallel.

Next time I get a load of stuff professionally printed I'll see if I can tack a few dual channel switch boards onto the order (they'd also be used for single channel switches; just leave some of the components off)