Again it's a question of definition, isn't it?
How many did Escom build, and how many did they sell. Was it JIT production for the market?
Hard to say. A lot of NOS CD32s exist. But they were for the most part built by Commodore and siezed by courts since Commodore lost that law suit (remember one of the triggering factors for why they went belly up?).
Commodore didn't do JIT production, I don't think so.
And Escom couldn't have been ready with their own production facilities and all to retool them for Amiga production, probably they just used the same as Commodore did.
So they probably didn't JIT either.
So what's the gap between built and sold? I'm sure the number of sold must be quite low, remember - they were bankrupt too, and new owners weren't keen to sell stock taken over or restart productions...
No, I suspect the number of Escom A4Ts to be quite close to the number of Commodore A4Ts. Both in number of units built, and number of units sold. With perhaps a small edge to Commodore in units sold as there seems to be more NOS Escom units than Commodore units.