Great — here are Australian options for swimwear in large cup sizes (D through K), plus where to buy, brands to look for, and quick fit/shopping tips.

Where to buy (Australian retailers that stock D–K cup swimwear)

• Brava Lingerie — plus-size swim collection up to K cup; stocks Elomi, Curvy Kate, Prima Donna and others. (bravalingerie.com.au)
• Storm in a D Cup — specialist D–K cup boutique (online + Bondi/Woollahra store); carries Freya, PrimaDonna, Fantasie, Zoggs and more. (storminadcup.com.au)
• Shell Lingerie — stocks Panache swim tops and other cup-sized swim options up to K cup. (shelllingerie.com)
• Splash / Splash Swimwear — carries Freya swim (size range D–K) and other full-bust swim brands in Australia. (splashswimwear.com.au)
• Brava’s dedicated “K Cup” swim collection — searchable on their site and useful for narrower/bigger-back combinations. (bravalingerie.com.au)

Brands to look for

• Panache (Signature/Olivia) — constructed, underwire and seamed cups for support; available up to K in some styles. (shelllingerie.com)
• Freya — bra-sized swimwear designed for fuller busts (often D–K across ranges stocked in AU stores). (splashswimwear.com.au)
• Elomi, PrimaDonna, Curvy Kate, Fantasie — established fuller-bust lingerie brands that also make supportive swimwear (many stocked by Australian retailers above). (bravalingerie.com.au)

What styles work best for big cups

• Underwired, seamed cup bikini tops and one‑piece suits with an internal bra sheath give the best lift and shape. (shelllingerie.com)
• Wide, adjustable straps and a firmer underband distribute weight and increase comfort. (shelllingerie.com)
• Tankinis and one‑piece suits with built-in cups are good if you want coverage and support without a separate top. (storminadcup.com.au)

Shopping tips (buying online and in person)

• Book a fitting or virtual fitting where offered — many specialist retailers (Brava, Storm in a D Cup, Shell) offer in-store or Zoom/virtual fittings to confirm band/cup fit. (bravalingerie.com.au)
• Check the retailer’s size filters — many sites list specific AU sizes (e.g., 10K, 12J) and let you filter by cup up to K. (bravalingerie.com.au)
• Review return/exchange policies before buying — some speciality stores (Storm in a D Cup) advertise free returns or exchanges. (storminadcup.com.au)

If you want, I can:

• Search for specific styles (bikini, tankini, one‑piece) in a particular size (e.g., 12K) and show current in-stock options; or
• Find nearby physical stores in your city that stock D–K cup swimwear and give store addresses/opening info.

Which would you prefer?