Mancini and some others have kits to install the later Saginaw pump (thinner oval neck and smaller cap on top) in the place of the earlier pumps (round necks and larger caps on top). Bolt-on as the Saginaw pumps started in 1969 as OEM on Chrysler engines.
Might be able to re-seal your pump. Especially if the fluid is coming out from around the reservoir can (which is a big o-ring type seal). Might be problematic if the fluid is coming out from the shaft behind the pulley (which can mean the existing seal has worn a groove into the shaft, like a front crankshaft seal can do). I'm not aware of any similar "sleeves" for the power steering pump shaft, though.
Your judgment call. DO make sure you have Chrysler-spec power steering fluid in the system. Every car I have had which came with "red atf" in the system had seeps. Putting the OEM-spec Chrysler/GM fluid in the system stopped them. Just my experiences.
The best long-term fix might be to do the upgrade. The re-seal can be variable, to me. Your judgment call. Using the correct fluid in any case.
CBODY67