The Imperial Gunnery is having a big update.
The Bespin Blasters is part of the work in progress.
This old picture:
V5 is easy to spot it has the 'rounded' trigger guard all the others have the 'square' guard.
V1 has the thick tip & very wide handgrip.
V4 has the long straight slot just above the trigger guard that stops before the 'bump' in the sight. (all the others the slot stops at the 'bump' )
V2 & 3 are undergoing further research.
Hope that helps? So your top blaster is V4, the bottom one perhaps is V1.