Go to:
http://www.antiquesurveying.com/rp_knives_______________by_rober.htm for knife information.
...or maybe Miles Welze (http://www.mileswelze.com/) knows more about him. (Miles sometimes sells his knives.)
Robert Parrish works on Antique Surveying Equipment now; his website (http://www.antiquesurveying.com) was last updated July 1st, 2017.
His address is Robert Parrish, 271 Allman Hill Road, Weaverville, NC 28787-8510
His email is: robert@antiquesurveying.com
Hope this is some help.