Gunny,
Check Doug Pecks parts Listings that I pasted below, not sure if any of these have the same size drivers as the Berkshires.
STEAMERS: GENERAL | 1412 | PULLMOR TRACTION BAND, for Steam engines; Thin band for flat rim (each) | $2.50 | |
STEAMERS: GENERAL | 1420 | PULLMOR TRACTION BAND, for replacement on "Flyonel" MIKADO, CHALLENGER, & BIG BOY steam drivers (each) | $2.50 | |
STEAMERS: GENERAL | 1519 | PULLMOR TRACTION BAND, for replacement on "Flyonel" Northern steam drivers |
Aflyer