HK P7 is not blowback. It is "gas-delayed blowback". Huge difference.
The very very few HK P7's that were somewhat "straight blowback"
are are no longer in production, a true rarity,
since long in un-accesible collections, extremely expensive.
You will not find one.
Try the Walter PPK in 380 ACP that had
a longer barrel installed to make it restricted.
Make sure the gun was not a 32 ACP converted to 380 ACP,
because you may have bad news (legally) in the following months.
If you have money to burn, you can try a Makarov.
It is an excellent design, simple, built like a tank.
The downside is the ammo availability.
It's almost impossible to reload cheap (9mm Russian is in fact 9.2mm), and
almost impossible to find a pistolsmith in Canada able to
make a quality, guaranteed conversion to 380 ACP.
Again, a rare and expensive gun is
the Steyr GB (gas-delayed blowback),
but that is a large frame, full size pistol.
My choice would be a
PPK with a restricted barrel that came from factory in 380 ACP.
Stay away from 32's converted to 380.
My 2c.