Crimson:
I can't see enough of it in your photos to make a positive ID and what I can see is confusing. The external cap on the cylinder makes me think Heil but the fabricated lift arms don't. They are more remeniscent of something from the south or maybe that old Smith outfit in Kansas City. That is my best guestimate at this point. See if you can get a good photo of the pump which may help with some clues. It is very likely an original setup to your 63' truck and the MO address points me at Smith so far.
Incidently the subframe appears to be bent upward and a very large gap between it and the truck frame. Might want to look that area over for damage. Could be the photos however.
