From the research I've done there isn't a set rate, just a percentage. It says Rev code 658 must be billed for hospice room and board services, and to quote the manual :
Hospice room and board services billed with revenue code 658 are reimbursed at 95 percent of the Medi-Cal Nursing Facility (NF) rate of
the facility where a recipient resides. You can do a google search for Medi-Cal "hospic bil cd" and it should bring up the part of the manual that explains it. Unless you're billing for professional fees that aren't related to hospice billings? There's plenty more information in the manual, so I hope this helps!!