That's a neat use of an old stove, and I doubt if much harm was done in the conversion to a floor lamp. Those smaller stoves without nickle trim show up at times around here in the $100 - $200 range.
The converted lamps started out originally as "nickle plated, round wick, central draft, kerosene lamps". Both were probably manufactured by Bradley and Hubbard, sometime in the early 1900's. The trademark "Rayo" was used on the lamps that B & H made under contract for Standard Oil Company.
The stripping, polishing and converting of those lamps was standard operating procedure for many antique dealers at one time. Most of the value today would be as a usable decorative lamp.