340 Piston identification. Silvolite?

badger has been gone 20 years
no real use for those slugs unless hooked to a more stroke crank- maybe even a 360
do the math
else for Mexican gas?
I just sold a set where in a 71 duster I had.
Ran it with a Crower hyd cam w/EDM lifters I'm going to put that up for sale now since I quit running hydraulic cams.