Try getting all those old parts to a facility, test them, assemble a consistent product, and get it out the door. Their efficiency in doing that is their value proposition.
I agree with you on the testing; if it's rigorous enough that will likely the biggest sale point.
One quote from the company and a definite (back to base) guarantee would be more acceptable to accountant than lots of small transactions on ebay/local suppliers.
We're talking about a use case where spending $500 to ten-tuple a users peak computational ability is too much of a capital investment and/or labor is too cheap to bother, so just hire more bodies and work slower.