I pulled over to the side of the road yesterday (Fri night) to park my CX5 along the side of the road, turned the wheel to get myself closer to the curb, then heard a loud pop/bang sound. Went out and saw that my passenger side front tire wasn't turning as it wasn't attached to the ball joint.

  
Had it towed to a local mechanic that's open on a Saturday as I wanted the fix done ASAP. Talked to them this morning and they're saying I have to replace the ball joint and axel. Said there's lots of rust that likely led to this happening (I never got any rust proofing). Attached are some pics of what things look like.

  
They're looking to charge $3,200 to replace the one side ball joint and control arm + axel. Then another $800 to replace the other side ball joint and control arm.

Since the car isn't driveable, I think they know I'm kinda screwed unless I pay to get it towed to another place. Do those costs sound reasonable?

It looks like the car is only worth maybe $4-5K based on online quote from Clutch, if it's still driveable and depending on condition. I'd likely spend the $4k to get both sides done, as I assume if it happened to 1 side, it's just a matter of time for the other to go... I'd likely pay this just so we have a 2nd car still (have 2 kids to schlep around).

I'm in Ontario, Canada for pricing reference.  
Any thoughts/opinions would be appreciated... I loved my CX5 and was planning on a new one next year  
Thanks!

2013 CX5 Repair quote - is this bonkers?