I know this is an OLD thread but I have the exact same question for the exact same printer/hardware rev/software rev.

Does anyone have any info on how to get the existing source for what comes on these machines by default.

I know the Ender pro is long in the tooth but it seems like Creality doesn't care about it at all but is still selling tons of them.

Got myself a new Ender 3 Pro this week and have a couple questions.
Marlin version 1.0.1
Board revision 4.2.2

#1) Do some Ender 3 Pros come with a all metal hot end, if so how can I tell if it is all metal or not?
I ask because the hot end in mine is solid silver and not the normal red that I have seen in videos or with the CR-10 I used to have.

#2) Which firmware should I be using?
Ender-3 pro 4.2.2mainboard--High Temperature Full Hotend Kit firmware.zip
OR
Ender-3 pro 4.2.2 mainboard firmware（32 bit.zip