Speaker replacement help

A friend of mine gave me an old hartke 4x10 cab that had been upgraded with Eminemce Delta 10b speakers about 15 years ago. It was beat up, torn tolex, stains in the speakers, just beat up. Sounded great though but heavy as hell. He was not using this cab and it was under a pile of junk in his garage.

So I went to work on the cab, took off the tolex and out on a nice duratex finish, new handles, corners, casters... Looks fantastic for a small investment of about $40 and some time, which I have in the summers being a teacher. I've always been a guy that if I borrow your car, I give it back with a full tank of gas. Thought it would be a nice gesture when I had to return the cab.

When re-installing the speakers, I jabbed my screwdriver through not one, but 2 speakers and left a nice hole in each. Now I am obligated to replace them. Should I just get replacement delta 10bs? The way the speaker is wired, using 4 16ohm speakers, it is an 8 ohm cab. If I replaced all 4 speakers using 8 ohm replacements (basslites maybe) and kept wiring in tact, would this now be a 4 ohm cab? There is no tweeter in the cab. Ther is no crossover. Just 2 input jacks with jumpers soldered between them. Set of white and red cables runs off of each input jack to the 2 sides of the cab. Black wire from speaker to speaker.