The internet is full of schematics for such relatively simple linear supplies. The costs would be the mains transformer, DC smoothing caps and then your current/voltage monitor.
You didn't mention current capability, which determines the size/cost of the transformer. Also, housing should be carefully done to ensure you're grounding exposed metal (but you could leave the supply floating). All of this is cost and hassle that makes the cost of a simple power supply quite reasonable. With that said, I'm sure we've all made DIY PSU's, and its a good exercise.
This bit:
A bonus would be adding a circuit that trips when you go over your CC, that I have no idea how to build electronically.
CC is constant current, that is, the output is regulated based on current flow, so the voltage is limited only by its maximum output (so the load determines the voltage). You can't go "over" your CC current, since that is regulated. Are you talking about current limiting, as in, fold back? This isn't the same.
I would like to see it built with LM317 or lt380 to keep it simple and analog
Again, because both devices are quite old, there are many many web pages detailing projects using them. You can find one, prototype and test with a separate power supply first (like a DC brick). It sounds like you have a pretty decent power supply, with 35V @ 5A with CC/CV. What features does it lack that you require?