I've experienced the same thing...
Yeah, discontinuing parts is the best way manufacturers have of killing off older, otherwise serviceable, high quality machines, so they can rope unsuspecting consumers into the two-year replacement cycle with POS bagless plasticrap vacs, which are more profitable for them than selling replacement parts and consumable items like bags and belts.
I had to get a replacement switch for my Legend II a few years ago and found a decent deal for a new one on eBay, albeit in black for a Heritage II. About a year and a half ago, I needed one for a Heritage 1HD and they were unobtainable at that time, although used switches for older Classic/Tradition era machines were readily available and would have worked, but it would have required me to replace the cord. Fortunately, a member here helped me out with one from a parts donor machine they had. There always seem to be people on eBay, parting out working machines because they feel they can make more money doing it that way than selling it complete. It's often a matter of snagging the part you need before someone else does.
Then again, if you keep a watch out at thrift shops, estate sales, etc. you might end up a similar machine at a below-market price. You can let one serve as a parts donor for the other, or even use parts from both to build the best machine you can from the two and have a bunch of spares left over.