Adding storage in my attic
How much insulation? What size are the framing members in the floor?

1953 house, unless it has already been updated, is probably in desperate need of more attic insulation. That will cost you money all year, every year until it's done.

Any house, plywood on top of the insulation will compress the insulation and cause it to lose effectiveness if the insulation is thicker than the framing members. And barring a few things you won't likely find in a 1953 house, the insulation probably should be thicker (potentially quite a lot thicker) than the framing members.

Finally, an attic that was built as insulation-only, no floor may not be up to carrying much, if any storage load. Your "ton" of storage may come down on your head.