Do special procedures exist to limit pilot workload during pilot incapacitation? Although pilot incapacitation is rare, the website avherald.com lists several occurrances of flight crew incapacitation, alone two events reported yesterday. 

FAA AC 25.1523-1 requires all aircraft to be capable of operation
by one pilot only from either seat, so just one pilot can safely fly the aircraft - albeit under increased workload.
In case of flight crew incapacitation, do airlines (or regulatory bodies?) have dedicated Standard Operating Procedures (SOPs) for the remaining pilot? Obviously, the pilot would declare PAN/Mayday and assess whether it is safer to land asap or continue. Or are there no special procedures because it happens so rarely?

Are there any procedures to limit pilot workload in these instances, such as shortened procedures, ask a cabin crew member for assistance such as reading checklists, any support from the ground / airline operation center...? The remaining pilot must execute all tasks of Pilot Flying and Pilot Monitoring, which means heavy workload during final approach.
Well, as a catch-all there is always FAR 91.3 which says he pilot in command can deviate from any regulation if they deem necessary in time of emergency in order to safely operate and land the aircraft. Obviously there's a reasonable limit to that and you'll be asked to give a report to the FAA on what happened, so be ready to defend your actions.

I can't comment on airline company procedures, but I have to assume there is a plan in place for this scenario since it is so realistically likely to happen at some point. I believe another crew member would be asked to help with simple tasks like reading checklists as you mentioned.