agree valmont it if J.F & SS, EP.
Haven't found a maker for this yet.
EP means electro plated - which means a think layer of silver over a base metal body thus silver-plated!
You might want to search dessert set forks and knives to get an idea of the ballpark yours are selling for now. Seeing alot of these popping up for sale lately. Being boxed helps some but doesn't give the value alot of boost. Depending on where you live makes a big difference and selling after February will help boost $$ a tad bit. Also, when comparing yours - make sure you compare silver plated and not sterling silver!!
The only JF I can find is Friedman Silver Company but they are a "J Crown F"...so that isn't it!
These can sell anywhere from $30 to well over $150. Depends on day. Since yours has hallmarks (even though I cannot identify) they most likely will sell on the high end...if in excellent shape!