The toilet can flush, but no water comes out of about 1/3 of the holes in the rim. The holes with no flow are in the front, primarily, furtherest from the tank.
I did try emptying the tank and bowl of water, then sealing all the rim holes and jet with duct tape. I poured about 1/2 gallon of vinegar into the overflow tube. However, vinegar started appearing in the bowl about 10 minutes after I did think (just a little at first) - obviously seeping through the tape around the bottom jet hole.
I let it sit like this overnight, then removed all the tape and vinegar, and picked at the holes with an allen wrench. None appeared to be blocked to me.
The bolts & washer holding the tank to the bowl did rust a few months ago (causing a leak from the tank) - I am nervous something got into the rim that I may not be able to dissolve.
Any suggestions? Or just time to buy a new toilet?
(If so - how hard are they to install?)
It sounds like mineral deposits as a result of hard water. If it's clogging the toilet, it's clogging everything else. You might want to look into a water conditioning system. which will remove most of the issue.
For the toilet, you can use a thin wire to clear the holes if you want to go to the effort. Putting the wire in a cordless drill will speed up the process.