I would not use 50 year old leather seals, why don't you check these out for the correct size. I believe NAPA sells Chacago Rawhide seals.
38 to 48 Ford one piece rear Hub 78-1175: Victor 49024, National 416738, Chicago Rawhide CR-20538
2.846 OD x 2.063 (shaft) x .438
35 to 48 Ford Front Hub 48-1190-A: Victor 49187, National 471316, Chicago Rawhide CR-15707
2.69 OD x 1.563 shaft x .313 wide