Found these on eBay. I believe these are made in the US. I offered $27 for four of the LR-2000 and got them.
4 Pcs Lot Unisorb LR-1200 Series Machinery Mounts Max Load 1200. Specs In Pics | eBay
4x Unisorb LR-1200 Series Machinery Mounts Max Load 1200. Specs In Pics. Condition is "Brand New". Shipped with USPS Priority Mail.
www.ebay.com
Lot of Four Unisorb LR500 Mounts | eBay
Lot of Four Unisorb LR500 Mounts. Condition is "Brand New". Shipped with USPS First Class.
www.ebay.com