Unknown Ferrea Valves

I'm taking my 915 J heads apart to clean (and inspect) as part of repairing the spun #8 rod.

The exhaust valves have "Ferrea F51151", the intakes have "Ferrea F51150" on them. All markings are near the tip. So far, I only have 8 out, but I've had them all out before, and the other 8 will be the same. I'm not the original builder, and have no history on it.

When I Google the name and numbers, nothing comes up. I would think that even if Ferrea changed their product line/part numbers, something would show up, somewhere.

I don't need any specific info, but I just wanted to find out about them.

They're 2.02/1.60's. The stems are all between .3711 and .3714. They're just a bit longer than 5". (About .070" longer, I don't have a good way to measure exactly.)

Anyone familiar?
View attachment 1716433554

Im guessing f5151 and f5150 valves in their catalog.
Chrysler 340 & w2.
3/8, 1.60, 5.075
3/8, 2.02, 5.05