Hello again!
So today a new ad popped up, it's a Philips PM3315 125MHz, 2 channel 'scope with 3 waveform memories and good amounts of trigger options for less than $90. The tube seems bright and consistent, the chassis looks extra clean but the seller says that some volts/divs need calibration and they're a bit off and he says the main power button sometimes doesn't turn it on and it can probably be fixed with some cleaning. It doesn't have any probes though. I don't know, do you guys think I should just go for it and buy separate probes? (Most probes available are Chinese with crappy plastic ) I can see a 60MHz Taiwanese probe for about $20 and from the same company but 250MHz is $50, more than half the price of the scope LOL.
First, that's a REALLY good price in my opinion. HOWEVER...
From my experience I can tell you that calibrating a scope normally requires pretty precise function generator and other gear. This is especially an issue when it comes to >20 Mhz scopes, because you start getting into the terrain of reasonably high-frequency signals where no cheap instrument will dare tread.
In fact, this is something I struggled A LOT with, when I had to calibrate a 100Mhz analog scope. The HF circuitry was reasonable complex and required gear I didn't have. I ended up cobbling together a high-frequency square-wave generator myself, and verifying the readings against a 100Mhz digital scope, which is definitely NOT the way the service manual recommended. At most I can say it ended up "more or less as poorly or well calibrated as the other guy"
So buying that scope might end up buying yourself a week (or more) of quality time with the scope partially disassembled over your dining table while you desperately try to come up with the signals and measurements you need to verify that it's performing as expected trhough its full bandwidth.
Regarding Chinese probes, some are pretty decent, to be fair. I have bought a couple sets for different scopes, and I'm yet to find a reason to complain about them. In fact, I'd say the last set I bought seems to work better than the probes that came with my Rigol scope (that doesn't make them good probes, but at least makes them better than what Rigol considers a good probe set for their entry-level scopes). Just make sure they are reasonably above the scope's bandwidth to avoid problems with the conversion ratio between "real Mhz" and "$20 with free shipping Mhz".