Before I started using my current digger I had one very much like the one your old timer has.
It was a pick/mattox and a short handle tool. Had a wood handle that was about 14 inch long.
I actually broke the head while digging seng in some very rocky/bluff locaton. It cracked thru the handle hole and was a goner after that.
That is when I got my new (old) digger and put a long handle in it. It had been hanging on a nail on a shed wall for years and I had looked at it a few times and thought about trying it for senging, then when my other one broke I did just that.
I had never used a long handle hoe like that before but as soon as I tried it I was hooked. I would never go back to a smaller tool, or short handle tool now.
The specs on my tool/head.
It has one blade that is 3\" wide by 5.25\" long and the other blade is 1.5\" wide by 5.25 inch long. It is light but strong. Not sure exactly what the head weighs, but the entire tool including my 36\" hickory handle weighs 2.7 lbs.
I hardly ever use the 3\" wide blade for seng, but it works Ok for goldenseal but I don't dig much of that (too much like work).
I think the ideal head for a hoe type seng digger would be a pick mattox type with a 2\" wide blade on one end that was about 5-6 inches long, and a pick on the other (long narrow blade) for getting into those tight spots.
It would need to be very strong but only weigh about 1.5 lbs.
I have not had any luck finding that.
You can find 2.5 lb pick mattox tools, but when you add the handle it is just too heavy for my liking. Lowes has one in stock that has a fiberglass handle but I checked it out and it was just too heavy for my liking.
PS - that website with the tools and hoe heads, I had actually found that back in the spring when looking around for a seng hoe head like I am looking for. They do have some nice quality looking tools but not the seng digger I am looking for.
I am very happy with what I have now but if I could trade that 3\" wide blade in for a pick blade I would do that.