When I acquired this, the grips were slathered with a horrid dark red paint. Fortunately, they were easily stripped with some acetone, revealing decent walnut underneath. All that was then required to complete their restoration was a light application of vintage boiled linseed oil. While they fit beautifully, I can find no mention of these guns ever coming with anything other than molded hard rubber grips, so it must be presumed that these are later replacements. I feel they actually constitute something of an improvement on the originals.
Here's a link to an article regarding this model: Harrington & Richardson's Self-Loading Pistol - Shooting Times
Here's a link to an article regarding this model: Harrington & Richardson's Self-Loading Pistol - Shooting Times