I can help you with the valuation of your set. The letters EPNS stand for electro-plated nickel silver which does not have a precious metal meltdown value value like sterling silver. The A1 designation is a stamp indicating they used the top quality material for the plating. EP stands for Electro-Plate, which is essentially the same as electro-plated nickel silver. HHS is the maker mark, possibly Henry Hobson & Son. Ivorine and Mother of Pearl handles were used mainly in the 1920's -1930's. In general real ivory would not be used on electro-plate and is more likely ivorine, or a celluloid material that looks like ivory. The number of pieces in the set does establish the value, however most EPNS sets with around 100 pieces in box sell for an average of $60 - $100 on today's market.
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