Buy a petrol powered pump if you are that worried. As others have pointed out, a scuba
cylinder would only run a pump for a few minutes.
Also, very few scuba
divers would ever use 100% oxygen on their tanks
. This is solely used by divers who are doing deep dives and using to cut decompression times or add a safety
margin. Using 100% oxygen deeper than about 7 or 8 metres will kill you!!! I would estimate that less than 0.1% of divers will ever use 100% oxygen.
By the way, I do know about these things, as of today I have done 3,730 dives, and on quite a few of these I have used 100% oxygen.