"if he is happy with it" Ah, I see.
Well, good to know it's possible at least. Did they mention if they will refill random customer-owned CO2 extinguishers, and the cost?
Do you know what the expiry span of the cylinders is? Any?
Hopefully not like propane cylinders, that are not legal to refill after ten years of life. At least not without getting them pressure-tested, but there don't seem to be any economical channels to actually do that.
I'm not worried about life, provided they comply with Australian standards (and they do), they should last well and truly for several years. I think in my entire time as a firey, I might have come across one extinguisher that leaked and there is no guarantee that it hadn't been discharged previously.
I'm using them in my own personal lab. I can conduct the inspections myself to my own satisfaction. I care not whether it's "legal". At the end of the day, if the thing is charged, I squeeze the trigger, CO2 comes out.
I didn't ask them about refills. Even if they aren't refillable, if I have to spend a few hundred dollars in 10 years time to replace them with new ones, money well spent. I spend more on coffee throughout a single year.
They are pressure tested when they leave the factory at pressures well and truly beyond their charge pressure. That will do me fine.
I'm not being coy because I want to be, but because I don't know the reasons why someone can't just walk in off the street to Bunnings (or whoever) and buy one of these. It seems like bullshit to me and I doubt there is any legal reason for it (I have asked the company specifically this and am waiting for their reply). This company is doing me a favour for reasons members of this forum don't need to know, but if they are happy for me to promote their brand, I'll do so and share what I've learned. In the mean time, I don't want to name a company who might not want to be named (for whatever reason).
The only thing I'll say at this stage is they have distributors in most states in Australia and are a wholesale provider of fire fighting equipment to various organisations. A little bit of Googling and simply asking the question will probably get you similar results, without having to resort to paying something stupid like $200 for a 2KG extinguisher off some online-only store.