Price is in the wallet of the buyer. As with all sales, the final sales price will vary with location of sale (ebay, aapk, craigs list, etc), condition and timing.
In general, the "obviously used" L66s usually go for $12 to $40, depending on general appearance, sheath originality/condition. Older ones like yours MAY bring a little more if you happen to catch someone looking for a "post-WW2 to End of Patent" period knife to fill a hole in his/her collection.
Used L39s are usually $20 to $50, again DOC. Newer "bright and shiny" knives CAN bring more as some collectors are like jay birds, attracted to only shiny geejaws. Folks slap $80 to $100 on them and sit around waiting for the unsuspecting noobie to splurge.
Your L39, being a rarer bird, might bring $50 to $80 if you found someone looking for a knife from that brief 1941 pre-war period, but then those someones looking for those era knives specifically are almost as rare as the knives themselves.
Now, on ebay who knows what something will bring. It might bring $30 and it might bring $230 because you had two or more folks with more money than sense all get hot and bothered at the same time.
The easiest thing is to stick them out on ebay at a decently low starting price and see where the market goes that week. There're a couple of sellers on ebay that start all their knives low, like $1 or $5, and let them ride it out to whatever they bring. That's one reason why the spread on used knife sales can be rather wide. Sometimes they go cheap and sometimes they sell in a bidder's war.