I think you would have to contact wormbase directly to get the version associated with WS182. However, I think it's identical to the WS180 version. I will give you a link to the 180 version here:
ftp://ftp.wormbase.org/pub/wormbase/species/c_elegans/sequence/genomic/c_elegans.WS180.genomic.fa.gz
The reason I think it's identical is that both the annotation details for WS181 and WS182 say "there are no changes to the chromosome sequences in this release". You can find those notes here:
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