I found them on Kogan at a decent price, but the shipping cost was just silly ($50sh); I also looked at eBay/Ali, but decided against it due to shipping delays being common in the past few months.
I ended up buying one from TradeMe, and it works fine. These cheap Ali/eBay/TM ones appear to be incredibly similar to ones sold for way more from some of the sites you listed; I'm really doubtful it's worth paying this much more, unless you really want a particular brand or style (eg, the triangle style of a Theragun).
This is the model I bought (for OOS/back pain - not exercise recovery, he adds quickly!): https://www.trademe.co.nz/health-beauty/massage/massage-equipment/listing-2752632716.htm?rsqid=4623bedc679f458597d5b3c48bb56080-001
Went with the same one you got from Trade Me. Arrived yesterday, full on massages last night. Great value so far so good.
Thanks for the tip.