Call your local appraiser and ask what their prices are. For a
referral, you can call ISA or ASA (18002VALU, I think) Both have
websites. (Those are International Society of Appraisers and
American Society of Appraisers.)
They should be a GG and have had training with ISA or ASA and
ideally have taken the USPAP course recently.
Is it worth having appraised? That's up to you. Is it worth
learning more about and documenting this irreplaceable family
heirloom? Could be as low as $50.00, depending on where you live.
Chicago area, Illinois, USA
Certified PMC Instructor