You can’t judge by looks since many look identical. Same shells, same coverings, some SuperDs are marked with a Dallas tag, etc. The back plate usually tells the story more than anything...other that pulling the amp out of the shell.
The Original Sewell is not a Dallas variant, so, at least IMO, not in the same wheelhouse. But, then again, the differences between the Dallas and Super Dallas are just about as monumental with a completely different power stage. Warren certainly did sport a Super Dallas - and probably one of the very first - for quite a while. David Grissom told Doug that the SuperD was the one to beat. Until he came up with something “better”, that was his amp choice from PRS. Obviously the signature models followed (DG also loved both HXDA variants and recorded extensively with them, too).
Warren’s biggest secret with his amps is his pedalboard. Farmer always dialed-in the amps to their sweet spot and Warren did the rest with dirt boxes and guitar volume (watched him do that up close). Even when playing provided back line for a small venue (Deluxe Reverb combo), he sounded just like him.
I’ve studied several shows where *I think* he’s playing the SuperD and it sounded glorious. The settings were somewhat visible and even a buddy of mine sent me pics from the stage! If you’re pursuing one of his sounds, the SuperD can get you pretty close. Finding one is a totally different challenge.