A non-standard or variant plural of 'haler' (one who hauls), using an alternative spelling.
This appears to be a non-standard spelling or variant form lacking documentation in standard English sources; it may represent a regional or obsolete writing convention.
English spelling was wildly inconsistent before the 1700s, so 'halerz' might represent how someone actually spelled 'halers' centuries ago—a reminder that standardized spelling is a surprisingly recent invention.
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