Please pardon the vulgarity. The title seemed appropriate. I am dismayed to report that the Sears dis-Service Center was as unhelpful as I'd anticipated. They do not perform any repairs of sewing machines on site. The machines are sent up to Seattle but they could not, or would not, provide us with a phone number to contact said shop. Meaning we could not speak with any knowledgeable person. My next thought was to contact a local OSMG and see if he could give a part number for the needed tool or maybe even order us one. I found the name and number of a guy but had the husbeast do the actual calling. In my experience men are more likely to cooperate with men as far as divulging useful information. The fellow related that the tool in question is no longer made and next to impossible to locate. However, he did share his method of removing those pesky pentahead screws. He uses a dremel tool to carve a slot in the head so it can be removed with a screw driver. The husbeast had been meaning to buy a dremel tool, anyway. There wasn't much room to maneuver the tool inside the sewing machine and I was nervous as hell, but he managed to cut the slot and now the screw can be removed. He ran out of time before he had to head to work but tomorrow he'll visit Tacoma Screw and get a replacement.
This is the wrench he modified in an earlier attempt to remove the screw. It didn't work because he couldn't get it in close enough. But he gets an "A" for effort.
Tomorrow we'll adjust the timing and replace the screw. Should be back in business in no time.