One point not lost on the more imaginative is that with any part which doesn't carry a serial number (and most small parts don't) you can use the paperwork which came with the previous one
This enables you to purchase e.g. spark plugs from the USA. People like Aircraft Spruce try to con foreign customers (Brits, generally) out of $60 per item for an 8130-3 - a total ripoff. A lot of companies can't even supply an 8130-3. A lot can but only because they have an in-house inspector which can sign the piece of paper.
It's the same as the JAR145 scam - a JAR145 company can issue a JAR1 form for anything; they just need to look at it and fill in the form. I was quoted £800
extra for a certain engine part with a JAR1 form; the part is merely weight selected for dynamic balancing i.e. is not even touched, and the US company which does this charges about $100. $100 to £800 - not a bad margin and I suppose this kind of ripoff is what is needed to fund the JAR company approval. Another JAR145 company converted a $9000 prop (with an 8130-3 from Hartzell) to a £11500 prop (with a JAR-1 form from the JAR145 company).
Ultimately, this ripoff culture is
all that safety regulation has achieved.
To get the safety benefits (i.e. avoid counterfeit parts made of duff materials etc) all you need is a certificate of conformity!!! And they generally come free, in the form of a delivery note etc from the manufacturer...
You've got to laugh, because everybody up the supply chain has already fallen over backwards laughing at YOU.