USA and postage .. eBay has listings. as does Aussie Amazon.com.au Compare a few offerings by googling the part code for the one you want
You won't get them any cheaper with the dollar rate and freight now.
Eg
444-4213B
Note there are 4-5 different grades of Progressives for Rocket IIIs besides length in 11.5, 12, 12.5, and 13" length and colour options. 12.5" is stock.
13" is a much better ride if your not too short.
A base stock replacement 212 series, mid 430 and better 444s twin shocks and then there are the HP piggy back etc.
www.progressivesuspension.com
Eg
MSRP:
US$781.95
444-4213B
444 (BLK) CRZR 13"
Out Of Stock
Estimated Ship Date : 1/3/2023
www.progressivesuspension.com