We don't have synonyms for aulnage yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are ulnage and alnage.
(n) :
Alternative form of alnage. [(historical) Measurement (of cloth) by the ell, specifically, official inspection and measurement of woollen cloth, and attestation of its value by the affixing of a lead seal, as was once required by British law.]
(n) :
Alternative form of alnage. [(historical) Measurement (of cloth) by the ell, specifically, official inspection and measurement of woollen cloth, and attestation of its value by the affixing of a lead seal, as was once required by British law.]