Ask away Smithie!

It's a solid piece of steel with a bore bigger than the barrel.  It screws onto a standard 1/2' x 20 UNF thread on the short (320mm from memory) barrel, which is also fitted with an external steel sleeve.  So all very heavy with a positive lock at the breech.  The extension can be replaced with a moderator, either is needed to have sufficient length to cock the gun.

Try aladdinz.co.nz for the lower adapter block, it may be a modified version of one he sells although there was one similar he had available but hasn't been able to get hold of again.  The mount itself is from AliExpress.  I've gone away from that style though as they have a number of downsides compared to the standard style mounts. 

Yes it was.

Is this the gun you purchased?

https://collectorweapons.co.nz/product/106fdd08-3f85-494d-b1f3-7cba14325452

I started by looking for something “better”than the basic 4x32 that came with my first air gun.  With minimal budget and little experience I ended up getting a JackalHowl 3-9x40 with a BDC Reticle after seeing a number of positive reviews of their scopes on YouTube.  The scope cost me just under $90 and I also added a set of rings for around $35.  All up the scope and rings cost around $120 including delivery.  The scope seems quite well made.  Turret clicks are reasonably positive, the glass is very clear and the reticule is adequate.  The zoom control is smooth.  Initially parallax for this scope was set to 100 yards but I have adjusted this back to approximately 30m.  This scope came with flip-up lens covers.  The only issue I have with this scope is that the dioptric adjustment ring cannot be locked and so it is easy to accidentally move while using the gun.  The rings were pretty average.  Currently this scope is mounted on my Hatsan Carnivore after confirming with the manufacture that this scope was suitable for high powered springers.   Overall I am happy with this scope as it is adequate for what I use this combination for, seems to be holding up on my Hatsan and at under $100 is good value.  This scope is no longer available, however there are a number of similar scopes in the “JackalHowl”  range at CV Life.

This is  what the BDC reticule on this scope looks like

After briefly trying a cheap night vision on my Gamo, I purchased a  FoxSpook 3-9x40ao R4 Reticle Crosshair Scope for the Gamo which cost me around $58 including delivery   This has a Mill dot reticule and came with basic elastic lens covers.   While not a clear as the first CV life scope this scope still reasonably clear.  The zoom ring is smooth and the turret clicks reasonably positive.  With the adjustable objective on the front of the scope it is not practical for hunting so I normally leave this set at around 25 yards.  The dioptric adjustment ring on this scope is a lot stiffer and does not seem to move while in use.  This scope is currently on my Diana in a set of Sports Match rings.  While I’m happy with this scope and at under $60 I believe it is good value, I am contemplating replacing it with something better. This is what the MilDot reticule on this scope looks like.

What is that please?