That would undoubtedly be the son, George B. Spring III.
His father whom I worked with was a engraver of most everything metal,,jewelry, flatware, watches, firearms, etc. He had worked as an engraver for International Silver in Meriden at one point in his career but hated the monotony of the factory work. He was an excellent antique clock repairman too. He knew most everyone in the business it seemed and that afforded me a chance to meet Alvin White while I was there.
I found a little more info on his son, Geo. B. Spring III.
Came to work at Pederson Custom in 1973,,that's not long after I left there.
Worked there till they closed up the place in '75.
Took his considerable talent up the road to Hartford and worked for Colt's but only till June of '77. (I thought he was employed there longer)
Freelance engraver after that.
I don't know if he did/does any outsourced work for any of the manufacturers or not while freelancing.
Many did so when the Colt Custom shop was going full bore back in the 70's and 80's. They had many more engravers that they sent work out to, than actually worked in house doing engraving. That's common in the business.
Even the 'A A White, Engr' marked pieces done while White was under the contract w/ Larry Wilson and Herb Glass are not likely the hand of AA personally.
Many freelance engravers were recuited to do the considerable amount of work that was turned out. White himself did only the top show pieces or the pattern piece of a standard layout then used and copied by the other engravers.