Here's how I remember reading what another member used to refashion the rubber grip on razors that had them...just a common drugstore pen...happen to see one in my office today so took a pic. The rubber on the end can be fashioned quite easily:

Name:  pen_rubberfilli.jpg
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Size:  11.8 KB
Name:  pen_rubberfilli.jpg
Views: 124
Size:  13.6 KB