Fran, just a wild idea, there's always a chance your local computer-
shop could upgrade your current one.
What they could do is...replace the motherboard+cpu, maybe power supply if you're having problems.
MAYBE they could re-use the memory chips. Then they could put a graphics card in it too rather than using "Intel HD graphics" (on cpu).
That way you can keep the existing case, keyboard, mouse, monitor, maype power supply, maybe memory, maybe CPU.
I'd need specs on your current computer. But if it is more than, say, 5 years old, they'll probably swap out most of the other stuff too.
If they can save any $$$ you could put it toward a SSD + HD combo and, optionally, a lower-end graphics card (still better than "Intel HD") and/or 12 meg of RAM.