Maybe this will help - from the listing:
SPRINGFIELD ARMORY, USA
A .58 PERCUSSION SINGLE-SHOT RIFLED MUSKET, MODEL '1863 TYPE II', no visible serial number,
dated for 1864, with brushed bright (as original) 40in. barrel, block and blade fore-sight, twin leaf and aperture flip-up rear-sight, solid top-tang, plain flat bar-action lock signed 'SPRINGFIELD' and marked with an American Eagle device and the date, walnut full-stock, heavy iron furniture including three barrel bands retained by flat-springs, nose-cap and cup-ended ramrod, fitted with swivels, good condition