Searching for silent 220-110 step down transformers

[Sherwood 1,261]

The 220v - 110v step down transformers your tax dollars bought me have an audible 50Hz hum coming from the transformer and it’s driving me crazy. 
I’d like to source an alternative low-wattage (under 200) unit that will be dead silent for my listening room, but I’d like to know for sure it’s silent before I ship it all the way to Moldova and plug it in. 
Any d-_-b recommendations?

[dsavitsk 3,843]

All transformers hum. The less they are taxed, the less audible it is. So oversized is your best bet.

[luvdunhill 2,921]

I would perhaps see what Torus Audio can do here. Regardless, find someone that uses the Plitron LO-NO transformers - I imagine there is a step-down version.

[swt61 8,690]

[Sherwood 1,261]

Helpful information, gentlemen, thanks. 
 

I’ve not found any lono transformers with the right windings yet, but I did find a 500W Plitron step down converter that handles 220v-110v here: https://m.aliexpress.com/item/32979526968.html?spm=a2g0n.productlist.0.0.58bb3e80yKcyh9

I’m always leery of Aliexpress, but does that look genuine to you?

[Pars 1,421]

For $75? Very doubtful. The transformer alone would be more than that. And the one you linked is 100VA, not 500.

Edited September 3 by Pars

[RudeWolf 240]

If you know what you're doing, then any 1:2/2:1 trafo will do the trick. Just need to keep in mind the HF and current rating.