Which satellites or space probes ďof historyĒ could do it yourselfers recreate using currently available technology?
Lets assume itís a free ride and drop off in LEO. And launch weight is not a concern.
With the increased knowledge of time and modern electronics of all types readily available, a good chunk of the engineering has been done for us. Just look at what we can pick up in just a days shopping.
Computers, Radio gear, Remote control gear, Cameras (video and still), Solar panels, Rechargeable batteries, even single shot model rocket engines!
Myself , being an amateur radio operator for decades and in electronic repair for 30 years. I suspect I have all of the parts needed for a Sputnik in my junk box already. Just dig up a metal case and itís good to go.