Intermittent starting issue

[zoner]

I've searched almost all of the previous threads on this issue and while I've learned quite a bit about all of the various electrical gremlins that can be hard to track down, my issue seems to involve some, but not all, of this and a little bit of that but not that one thing...

Over the past week, I took Sabine on a 950+ mile trip around California- from the city to desert to the mountains to the coast. This problem (thankfully) didn't pop up until the last day of my trip when I got in the car to start it up for the drive home. Turned key, ignition turned on- all dash lights working, fuel pump working, would not crank. No click, no starter engagement whatsoever. Checked all fuses and checked for obvious loose connections, everything looked good. Tried jumping the contacts on the clutch starter switch plug to no avail (although, I'm not 100% that I was getting good contact on the plug). I'll back up a little bit and say that for the past few weeks, when I start the car, there is a noise coming from the starter for a second or two that sounds like the bendix isn't disengaging (like the starter gear is briefly dragging once the car kicks over). I was able to push start the car and it started right up no problem.

Drove about 75 miles with no problem until I stopped, parking it on a hill in case I had to bump it again. Turned it off and restarted it again (while it was still hot) about a half dozen times without a problem. Once it had cooled for a couple hours, it would not start again unless I bumped it. Drove it the rest of way home and once I got home, I shut it off and restarted it with no problem several times (car was still hot).

Got up yesterday morning and it kicked right over, but when I shut it off after idling for a few minutes, it would not restart. Got up this morning, would not start again. I put a voltmeter on it a short time ago and had 12.65 volts across the battery terminals. Positive terminal to chassis also yielded 12.65 volts, so it doesn't appear to be a grounding problem (I cleaned all of the terminals and connections just in case, but still no start and still the same voltage).

Given the noise that the starter was making prior to it not starting, as well as the starting seemingly being sensitive to engine temperature, I'm leaning towards the starter being the culprit but I'd hate to change it out, only to have the problem remain.

Has anyone ever experienced this particular issue or have any ideas of what to check next? (or have a definite way to check if the starter is bad that doesn't require removing it and bench testing it?) Thank in advance for any advice!