To the OP.
Cool. You are going to do bass. Maybe it is a solo/small group looper thang right now in the local Falafel palace, but next month you might be in a larger place with a louder band. Gonna find out whether or not your rig cuts it then? Here are some of my prejudices. Hope they help.
You would be well served with a 350 watt (minimum, 1000 is not too much) head, and a cab with a horn that can be attenuated. You will need a horn if you want clarity from chords played in the upper register. You will also need to attenuate it if it gets harsh with a distortion pedal.
A 210, 112x2, 212, 115, 410, 210x2, 115x2, 610 215, 412, and others all work, but avoid mixing 10s and 15s or other such things.
Think twice about so-called combos. An all-in-one combo will lock you in. If one part dies or is not enough, you are dead in the water or at best a fart machine.
You've set $500ish budget. My advice is two-fold. Raise your budget, and buy used. How high? $350ish for a head and $450ish for a cab. Look for Ampeg, Carvin (heads), Eden, Epifani (cabs), Gallien Krueger, Genz Benz, Hartke (heads), Markbass, Mesa. There are others, but I don't know them as well as those.
Skip the vintage gear thing. I am 64 years old, and have played all of it. Current stuff is (ALMOST) all vastly superior in one way or an other.
Don't believe anyone who says the driver size determines the character of the cabinet. Believe me, there are huge differences between cabinets, and much less difference between heads. Used stuff costs about 35-40% of new stuff.
Avoid 4 ohm cabinets unless they are Epifani UL1 410 4 ohm cabs.
It is hard to have too much power and too fine a cabinet, but if I had to choose one of those, it would the "too fine a cabinet." I am fEARful such things are hard to find.
Or just forget all this and buy a used combo.