The blade is marked with the maker 'WOOLLEY & DEAKIN' ^[1],  Birmingham makers working in Edmund St.,  Birmingham, 1803-1812.  The date on the blade is very interesting and unusual,  it is possible (though unlikely) that it relates to the partnership between Woolley and Deakin which began on the 30^th April 1803.  It is more likely to relate to a specific contract,  I have another example of a 4" Bess, but with India pattern shoulders made by Dawes,  also marked 1803 on the blade,  this example however has the worn remains of the East India Company heart mark.  I have also found another example by Woolley&Deakin marked '1803' but with India Pattern shoulders.

(1) British & Commonwealth bayonets by Ian D Skennerton and Robert Richardson,  page 398,  ISBN 0 949749 04 4