Whether or not this is a wise purchase will depend on your income and current budget. Like.....if you make $20-30k/year, this is probably too much. If you make $60k with no other big expenses, this is probably affordable.

Also, you list a pretty wide number for the repair of your current car. Who is estimating the cost to be $500-2000? The dealer? Did you get any other quotes? Why is the current quote such a large range?

In which case I'd focus on building up your education/job skills in a field that would allow remote work from home. Or, while you mention crutches, accept that a wheelchair might be a necessary option, and look for in person jobs that can accommodate you getting to/from the place in a wheelchair. I'm not naïve, and it will certainly be harder than it was before your injury. But people thrive in work/life with similar mobility issues all the time.

Honest question. Do you think you cannot work at all if you were confined to a wheelchair b/c you can't walk w/o pain?

If you're not working, there is little chance of qualifying for a loan. I also wouldn't take out a personal loan simply to boost your credit score a little bit. It's not going to suddenly drive up your credit score. The bank will care much more about you having a decent, long term job than whether or not you made payments on a personal loan over the last year.