The first question is whether or not your blade is actually valuable enough to justify the cost of sharpening plus shipping or transportation. Such will depend heavily upon the blade in question. It will likely also depend upon band length and tooth count as well as tooth material (hardened steel or carbide) and condition as to the ultimate sharpening costs (they likely take much longer to sharpen than most blades due to their high tooth count).
For most of us, hitting the occasional nail while resawing is just considered part of the cost of doing business in this hobby and we just replace the blade...and, potentially, the event becomes justification to possibly invest in a metal detector wand to scan questionable lumber for nails ahead of resawing (or you can present to be a security guard, your choice). Such things will happen from time to time.
But I wish you all the best whatever route you end up pursuing. Good luck! Please let us know how things turn out.