I've not seen that intake, but the motor has been around awhile under a few names, gt5 etc.
The 40mm intake brings better ports and port timing along with the wider front mount saddle for larger frame tubes. I have one like this sitting on my bench except it had no intake when I got it, so not sure it's the exact same motor.
This shows the wide intake needed for these jugs.
Been seeing the longer bent clutch arm awhile too, usually only on the better quality motors regardless of intake size.
If more is better, then too much is just enough.
If you can't afford it, build it yourself.