My objective is to create a tabletop Bell test experimental setup generating data of suitable quality for undergraduate education or satisfaction of personal curiosity; remaining free from loopholes or pushing fidelity frontiers is not a concern.
As has been covered elsewhere you need to be able to emit & detect single photons in order to measure quantum phenomena. You can buy the single-photon double-slit experimental setup "in a box" from TeachSpin for about $9500, which uses (basically) a dim lightbulb behind a filter to generate few enough photons that only one photon is likely to be flying through the apparatus at any given time. However, I suspect this would not be good enough for Bell test where you need to correlate photon emission & detection. What is the minimal experimental setup necessary for a basic Bell test experiment, and approximately how much would it cost? Thousands? Tens of thousands?
The only heralded single-photon emitter I can find online costs $22,000 by itself, but I suspect that price is more a function of convenience, quality, and niche market. I would expect to have to build one myself through a laser, SPDC crystal, and detector. In a similar unanswered question a user claims in a comment that a basic working Bell test experiment can be conducted "for cheap" (presumably a few thousand dollars). Has anyone considered this problem?
A related question concerns the price of components giving specific capabilities but does not cover a full Bell test experimental setup.
