Bosch is a good brand and that's a great price for it too. I would definitely buy that pump. I'd rather have it on hand than not when you pull the tank down.
If you're concerned that the leak is from the top of the fuel sending unit's hard metal lines, I would go to a junk yard and also get the plastic lines that attach to it. Each (two) of them disconnect at the front of the fuel tank. It's usually about a dollar/ft at a "you pull it" yard. I would also be concerned that the rust broke/broke down the rubber seals and/or the plastic clips, especially since it is leaking fuel. Depending on your experience with those fuel line clips, it could be an easy grab or it could take you 30 minutes.
You'll need either two small screw drivers and/or a few small pick tools. I'm sure there's a specific tool that makes releasing those clips a breeze.... I wish I would have looked for it before I pulled my tank. I thought it would be easy, but that was what took the most time in removing the tank, was pulling all of those plastic clips.
I just broke the small clips on mine. A pack of 6 clips is only about $5 at most parts stores, locally.
The large evap clips are $15-20 for 3 of them and they are plastic, so be careful with those evap clips. Or just grab a bunch of those clips from the junk yard as well.
It doesn't sound like you have any bad ground wire, I just mentioned that because you are going to be able to easily see them on the frame as you go under your vehicle. Because if your metal fuel lines are rusted that bad, then I assume that the frame or at least the ground bolts are rusted just as bad. The two grounds on the frame were rusted/corroded. I lost my 5v computer reference voltage at one of those grounds. I think it was the ground wire near the passenger's door that was for the 5v reference for the evap system.
Cleaning the ground wires was just a preventative maintenance suggestion is all. One if not two of the grounds could stop your fuel pump from functioning. I attached the ground distribution so you could see what all could go wrong if that ground is lost to rust/corrosion.
Sorry for the long post. I've just been there twice in a two-three week period and learned so much, lol.
EDIT: After/if you clean those ground wires and the frame where they connect to. Make sure that you also spray them with some battery terminal sealer as well. I used dielectric grease and that only lasted a few weeks. I had to clean them all over again.
I'm not sure if painting them once they are cleaned and reattached is a good idea or not. It was a thought I had, but didn't want to chance having to clear paint and corrosion anytime soon.