My 1979 240d keeps on moving, slowly.

I have been neglecting a bad left rear wheel bearing and today is the day I actually checked it and wow, I think one more mile and I would have had some pretty bad trouble.

My question is, given the expense of bearing replacement, what would be the collective opinion of getting a used control arm with hub and bearings ready to go and swapping it out. I put the car in the air in the garage and my axle comes loose from the hub and it looks like there isn't too much to it.

What should I look for in a bearing/hub assembly in a control arm without an axle. How much play is too much? How smooth should it feel?

I can get a complete assembly locally for about a 100 bucks.

I appreciate your input.

Love,
Mattmotor