OK, picked up the seal today. Looks perfect. It's ISP (International
Seal & Packing Co) www.intsealpack.com 1-800-651-2551

Part # R01220 Description: 16x28x7A NBR SEAL

You may not be able to order direct. I ordered thru a local pump
repair place. Just over $12 shipped. Seal was just over $4.

Will let everyone know how the pump goes back together.

Jim