Can I suggest you start with OpenSIMH - https://OpenSimH.org and try running any a simulated system.   It's a lot cheaper and while quite the same has having the the actual hardware, a lot easier to manage and most everything you could do from the old days can be done on you personal computer.   If you want BlinkenLights, get one on of Occar's wonderful PiDP11 kits - https://obsolescence.wixsite.com/obsolescence/pidp-11  (which run OpenSIMH behind his lights and switches). Again a lot small and will meet you budget constraints.

On Mon, Jun 9, 2025 at 2:08 PM Vicente Collares via TUHS <tuhs@tuhs.org> wrote:
Hello Milo,

On Mon, 9 Jun 2025 13:38:54 -0400
Milo Velimirović <milovelimirovic@gmail.com> wrote:

> What’s your budget and what’s your level of hardware technical skill? If budget is no concern, there are occasional complete pdp11 or vaxen on eBay. Or, you could get CPU cards and interfaces to piece together a system. If you go that route a Unibone or Qbone is highly recommended for both debugging and filling in hardwar gaps via emulation. Alternatively, there are several FPGA projects to emulate -11s.

Buying a complete PDP-11 or VAX is the dream, but it's not what I'm
aiming for to start. I was thinking of something like a UNIX
workstation. I haven't thought about the possibility of piecing together
a system using various cards. Thanks for pointing that out, I'll have to
look into it.

Budget is a concern for me. So ideally I would like to spend around $500
USD on the actual computer. Is that realistic for the type of computer I
mentioned above?

I'm not hardware savvy, so I would have a limited ability to do repairs
on the electronics. I do know someone who is though, so I might be able
to get some help on this project.

I wish you an excellent week,

Vicente
vicente@collares.ca