The two stamps on the right appear to be a Lion Rampant and an R in a shield. After doing some research here, my best guest is this is a Glasgow piece, and the date is 1836. Of course, I could be completely off base.
The unknown mark could be a tree or a bird, but the underlying mark (beneath the tarnish and scratches?) could be something totally different. I'm hoping that somebody might recognize this. Thank you! Dave

