Here are a few more points to consider:
1, Is the holder marked as well or only the nib? Freer could have made only the nib.
2. Is there a size number on the nib (2, 3, 5, etc.)? The larger the number, the more valuable the pen.
Generally, if you have a holder that is marked the same as the nib, the item is worth more. That is especially true if the maker is more famous than Freer, i.e Aikin Lambert, Mabie Todd, etc.
If the nib is a size 3 or less then the pen is probably worth less than $50. If it is a size 5 or 6 then perhaps $100. A better known maker would raise the value. This assumes good condition, iridium still on the nib and that the thing works