I bought the steering column rubber/metal floor cover w/seal '48-'55 3spd pair from Carters (Independence, MO) ($22.74 including shipping).
I installed it at the base of the firewall using fasteners bought at my hardware store.
I mounted the 2 piece caste iron clasp with the original hard rubber pieces using an original fastener and a replacement bought from my same hardware store.
Everything is not completely wrenched down tight yet cause I need to mount the shift mechanism.