Pac,
Thanks for the quick response!
When I get home from work I can try and take some clearer pictures. From what I could tell, I didn't see a number anywhere on the heel. I could have easily missed it though, the whole anvil seems to be pretty dinged up with tiny chips, cut marks, and divots.
My guess is there's a plate welded on top, but it's really hard to tell if it looks that way due to edges starting to go or if it's a weld line.
I don't have any ball bearings unfortunately, but I can try to pick one up on the way home, and hopefully find out what the bounce is for you.
Thanks,
Sean