The recent broken sideplate assembly thread got me thinking yet again about 3rd Gen replacement parts. For as many replacement parts as I've accumulated, I have yet to purchase my first spare sideplate assembly and I'm starting to see that it's an easily broken part... not by wear but more commonly by accident... with very limited (and likely shrinking) availability. I intend to rectify that mistake as soon as my tight budget allows.

My view is that some parts, like springs, will always be available from someone. Other parts will probably continue to be available from the mothership or alternative parts suppliers for some time to come. Some can even be made or adapted from parts for other guns. But then there are others that are already discontinued and unavailable from regular sources or hard to find except at a high premium price or with a long wait. Some are "special order" parts but I don't even know what that means in a practical sense.

So ignoring the parts that will always (or almost always) be available from one source or another one way or another... and ignoring the parts that are either very unlikely to break or that are too expensive to replace anyway... what are your critical "must have in stock" replacement parts?

I must admit that most of my less common spares have come from pure opportunity rather than necessity or some systematic approach or analysis of potential failures and accidents. That's not the best approach but that's reality. When I have the money and when certain parts I know I might need someday are available but might not be tomorrow, I buy them. It works to a point, but it would be much better to have an actual planned approach.