How to install zipper missing from guitar case

I got this bass guitar case for free from a music store with a guitar I bought and I'd like to try and replace the zipper. The case is in good shape and the zipper teeth seem to be good. How do I go about adding a zipper?

 

Do you sew and have an industrial walking foot machine or at the least, a very heavy duty machine? If you still have a shoemaker in the area, they would be able to do it for you.
I don't know of any other way to replace a zipper.
If you do sew, I can find instructions for you.

 

I have a similar case and was just looking at it. There's a difficulty level there. I wouldn't really want to tackle it myself. The best thing would be to take pics as you're removing the old zipper and then sew it back the same way, providing you have a walking foot or heavy duty machine. Is the zipper broke or you just wanted a new one? You said the zipper teeth seem to be good.
Another option would be to remove the zipper and sew in velcro instead. Might be easier than a zipper.

 

Maybe look at zipper repair parts. There are many on Amazon that you can see.

 

The zipper is missing. I do not have a heavy duty sewing machine.

 

It just occurred to me that maybe you're talking about the pull, not the zipper. The zipper is the whole thing with the teeth. The pull is the part that pulls the slider up and down to open and close the zipper. Is this what you're talking about?

 

Assuming the pull is missing, is the slider thing still there? If it is, the easiest thing to do is get a large paper clip or a keychain ring and attach to the slider. I don't think you can just attach a pull to the slider. The pull and slider come as one. You'd have to replace both.

 

It is missing the slider/pull. Can I purchase on and get it one? How do I determine the the size I need?

 

I'm only familiar with pillow type zippers, but I included a link here that tells you how to measure to figure out. The slider and zipper must match exactly.
Here's the link and about half way down, it tells you how to measure. It also explains different kinds of zippers and their uses.
https://threadsmonthly.com/zipper-types/#sizes
You're facing a couple problems.
One is you can't just buy one set, you'd have to buy in quantity.
Two is, there's no way to just put it on the zipper while on the bag. You'd have to remove at least the bottom part of the zipper to slide it on from the bottom, then you'd have to buy a new stop (again in quantity) to replace the old one. Then it needs to be sewn back (you'll need that heavy duty machine).
OR you could keep the zipper put and remove some of the bottom teeth, slide the slider on, but then you'd need a sewing machine again to sew across the bottom, under the slider, to act as a stop.
You need the stop or your slider will just slide off again. Perhaps you could try getting some extra strong thread and large size needle and hand sew it.
Not sure it would pay to pay someone to do this. Guess it depends on what they would want and how important it is to have this fixed. Might be cheaper and easier to just buy a new case.

ETA if you still want to do this, I think removing some teeth from the bottom and sewing a new stop by hand, would probably be the easiest solution for you. However you do need to know the exact size.