[LMH]

In general, Lucas toggle switches are not rare. Same for the Lucas rheostats for the dimmer. The momentary push button is available from a number of supply places like Finish Line.
That particular wiper switch/bezel is another story but if you're not too concerned with the bezel, there are other Lucas wiper switches/bezels that could be adapted. Lucas knobs are common on eBay as well as other suppliers.
Make sure you buy a Lucas bezel tool to tighten the bezels. They're easy to scratch w/o one and the tool isn't that expensive.
Larry