8.75 shock plates

USPS makes a padded Priority Flat rate Envelope that is great for heavy metal parts. Spring plates, pulleys, motor mounts easily fit in the bubble wrapped package which ships anywhere in the US for $5.35
https://store.usps.com/store/browse/uspsProductDetailMultiSkuDropDown.jsp?categoryNavIds=catGetMailingShippingSupplies%3asubcatMSS_PriorityMail&categoryNav=false&navAction=push&navCount=0&productId=P_EP14PE&categoryId=subcatMSS_PriorityMail