The sights don't hurt the value to some because they're a proven combination but I myself would take off $150 for them because I don't want fiber optic anything (yes, I have tried them) on any gun and I would want original parts. I have peep sights on my 336RC and my 39A but they are steel and from the 1950's. It's priced about $500 lower than average for my area. I'd pay $750, replace the sights with OEM, and sell off the aluminum and plastic stuff.
This is the first time I have heard someone call an 1894 light. Don't get near an 1892!