Would it be a safe assumption that over this period of time these pipes are becoming more rare on the market, and if so would that likely make some of them more valuable than the older sales records show? And, I'm also assuming it is better to sell them individually (ebay being the best place?), since I discovered consignment percentages of sale are quite expensive.
In the 12 years that I have been tracking prices on vintage British pipes, my impression is that by and large, prices on these have fallen by about 30%.
My guess would be that more expendable money is going into cellaring tobaccos before they become unavailable and less is going into buying pipes. Some of the action that was precipitated by Asian buyers has leveled off.
There are a number of factors that determine the value of a pipe, of which rarity is only one. Besides rarity there is the matter of condition, and how much of a market a specific brand commands.
For example, 10 years ago a Barling pipe like this one:
would have fetched between $900 and $1200 on ebay. Recently they have been going for between $600 and $900. And there are any number of similar drops in price among the major British brands, including Sasieni, Comoy, Charatan and Dunhill.
Prices have also softened across other areas of the market.
One other method of selling your collection that has not been mentioned is renting a table at a major pipe show, specifically the Chicagoland pipe show, and selling them yourself. One friend of mine did a good five figures at the last show. He did his homework, and knew what market prices were for the pipes he was going to sell. He priced his pipes attractively and sold a lot of them.
eBay can be unpredictable and results largely depend on providing an excellent presentation, the key to which is excellent photography. It just depends on how much work you are willing to commit to, vs how much your return will be on that work.
Selling off the collection en mass to a dealer is the simplest approach but it comes at a price. Dealers need to make their money and they're entitled to given that they have their money tied up in the stock they bought are will be making the effort to sell it. Consignment is another possibility, but you need to know what a fair evaluation is since you set the price. I'm not going to tell you what is your best option. That is entirely up to you.
But again, do nothing in haste. Learn about market values for what you have. There is no substitute for being knowledgeable.