if you can find an old box, cigar box whatever, chuck them all in that and place it in an auction house (it's a common trick from professional dealers)
but you'd have to have something of value, or really huge quantities, for it to sell.
people collecting cancellations and flyspecks often cherish these lots... if all stamps are pre 1940, you'll also spark interest from WW collectors that collect the first 100years.
i have this box, which I found on a yardsale, they are original storage boxes from the national museum.
sometimes I empty albums, because empty albums sell better than ones with cheap stamps in them. sometimes I have some leftovers from bulk purchases or some that are faulty.. I chuck them in that box and when it's full I sell it.
it has everything, classic Danish stamps, better stamps, good cancels and quite likely varieties for the flyspeckers..
Just describe your lot honestly... bulk stamps in old box, from classic to newer, better cancels observed and all qualities exist..
place it for sale at a very low starting price and let people decide the price after all, one persons trash is another's treasure.
I don't have duplicates, I don't have stock books, even though I attend the nearby stamp club meetings, and several times a year I go to stamp days around the country. It's my impression that very few people exchange stamps the old way - money is always involved.
so having stamps of value sitting in an album waiting on the chance that I run into someone who needs isn't worth it... better get rid of them for $ now, and buy what I want when I come across it.
inflation and energy crisis certainly proved that point - because a lot are selling from their collections now to pay the bills - and at the same time fewer are buying - the market is mine (evil laugh).