Today, you don't get a Fluke calibrator for the price of two 3458A
One factor you have consider when pricing a product is "How many of these do I expect to sell, over the lifetime of the product?". I am sure that HP predicted that they would sell a LOT of 3456A/3458A DVMs. So the development costs are spread over all of the DVMs sold (which were probably many 10s of thousands). How many 5700A units can you sell over it's lifetime? If the sales hit 5,000 over the lifetime I would be very surprised.
I worked for a company which made automatic test equipment for discrete semiconductors, i.e transistors, fets, diodes and so on. I think we may have sold 600 test systems over it's entire lifetime, which included many, many engineering changes and upgrades to the basic design. Our rule of thumb was to take the material and labor costs of the system and multiply by 3 and that was the sales price. So if the materials and labor cost $30,000, we priced the system at $90,000.
Bill