Looking for old toilet seat replacement

Hello!

One of our elderly customers would like to replace his toilet seat. He has a Kohler Rialto one piece toilet manufactured around 1988-1989. The plumber who went to the job advised me that the toilet seat does not have bolts but rather, anchors to the toilet. I've called Kohler, searched **** and the web and came up empty handed. The number the plumber wrote down from the toilet was K3826 but again, I got nowhere with that number.

If anyone has any ideas, please let me know. We'd love to be able to get this for our customer.

Thanks in advance.

How about k-3386?

http://www.kohlerserviceparts.kohler.com/ServicePartsPage.aspx?DocumentID=e4c966dedca445bd8f9932bda38b75bb&ModelID=8e94cd8ffe9346369ebfd550f5cde5fb

toilet

My 1993 book only has numbers to k-3546, and then it jumps to k-4300 so I wonder if that number was the tank lid and not the toilet. The Rialto in that period had k-3400 numbers.