Hi Tom,
This discussion will be of interest.
http://vikingsword.com/vb/showthread...ght=dutch+1815
I found the Dutch Army Museum very helpful and I think it would be good idea to get in touch with them re your musket. These muskets were based on the French 1777 Charleville and if you want a bayonet the French one will fit. I tried to track down a Dutch made bayonet but without success but the French ones are relatively easy to source.
Regards,
Norman.