Plastic chopping boards are normally just UHMWPE ( https://en.m.wikipedia.org/wiki/Ultr...t_polyethylene), so if you touched based with an engineering/ plastic supply shop, they should be able to sort you out with a custom size/ maybe even an offcut from a sheet. From a Google, these guys look local to you (if the big H = Hamilton), https://www.waikatobearings.co.nz/pr...ering-plastics
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