An officer, who can only be named as NX121, appeared in court last week accused of the murder of Mr Kaba, 24, who was shot once in the head in Streatham after his car was boxed in by officers tailing him.
While the officer is currently anonymous, officers are considering a protest if they are named, reported Sky News.
The anonymity order could be lifted by a judge at a hearing on October 4.
A serving firearms officer who spoke to the broadcaster said his colleagues could hand in their weapons if this happens.
“The anonymity hearing will determine what happens. If he loses his anonymity, then serious questions will be asked,” he said.
“I haven’t handed my firearm in yet, but I would if that happens - and there are many others that would do the same."
Two other firearms officers also confirmed the potential protest, Sky News reported.
It comes after the Met’s chief Sir Mark Rowley said firearms coverage was “significantly less than normal" after dozens of officers downed tools over the weekend after the officer was charged.
Speaking at the first meeting of the London policing board, he said: “Over the weekend, it had a very significant effect on our capability. We’re now in a position where the numbers are strengthening.
“We can provide credible firearms cover for London, but I must be honest, it’s still significantly less than normal which will create some difficult choices."
The military was put on standby to help with counter-terrorism functions and neighbouring forces provided cover after dozens of Met officers stepped back from armed duties.
Firearms officers are used for guarding key sites such as the Houses of Parliament, for proactive police operations and for counter-terrorism duties.
Sir Mark said the number who had stepped back from their duties had varied across the three areas.
On Monday afternoon the Met said it no longer needed military assistance after a number of officers decided to return to their duties.
Sir Mark said some were “extremely anxious" over the weekend, mainly driven by concerns from their families.
He has called for reform of the ways in which officers are held to account over operations involving firearms, other use of force or police pursuits.