Strategy: Go right to the source

My friend who is Polish ironically likes this brand, Pour Moi, which is a U.K. brand.  Their shipping is only £5.50,

Compared to Canada, international shipping is quite cheap from the UK, so these bras end up being cheaper just to buy from PourMoi.co.uk 

Pour Moi is a budget brand, so this boutique marks things up [kind of] unnecessarily high, IMO; if people want to pay 3x as much to have things readily available - that is their prerogative! However, if a person already knows *this brand works for them* and they're willing to wait 20-25 working days (about a month). 

It's a lot to pay for a brand that's made in China. 

LL Brand

 LL brand is the house brand (I believe) for Lavinia Lingerie that caters to Matrix Sizes. 

https://lavinialingerie.com/collections/vendors?q=LL

I believe they are made it Latvia, so I will tag them as ethically made. 

Lavinia Mystic Winter Light Semi-Sheer Lace Bra

Lavinia Plumy Floral Lace Plunge Push-Up Bra

Gorteks Marilyn - Sale Bra

Full-bust bra $27 + shipping 

 https://lavinialingerie.com/collections/marilyn-gorteks

Good for narrow roots, close-set breasts, FOB

To see other sale bras at Lavinia Lingerie, see this page https://lavinialingerie.com/pages/sale-up-to-80-off

Because these are European-sizing, it may entail a few back -and-forth exchanges to work out your correct size. *Unless you know you're sizes in Polish bras well, this is probably most affordable for U.S. shoppers, shipping is $3.99 in the U.S./$14.99 to Canada/$19.99 worldwide