You can't do just the glass. You'll kill the screen doing that. You'll have to buy a combo part if you want to do it yourself (which at this point is all you'll be able to do, since you ripped it open yourself).
If you really want to go ahead with it... Don't get some low quality junk part. I work in cell phone and tablet repair, and I have people come in all the time with broken parts of their phones that they tried to replace. Be prepared to shell out a **** load for a new screen.
This is the only thing I can recommend. We use Gadgetfix when we can't get parts from our usual suppliers, so I can vouch for quality.
For the screws, you can try to do what we do... Superglue. It sometimes helps you get a grip on troublesome screws.
Also make sure you have a heat gun. Hairdryers take a hell of a lot longer, but those work too.
Sprint Galaxy S5 SM-G900P
Samsung Galaxy Note 10.1