This bass came up for auction on Ebay in November 2013 with an initial asking price of $1,689, which includes free shipping. This one looks to be in pretty nice shape, with the OEM case and thumb rest, and with only minor flaking on the pickup. Here's what the seller had to say:
"Quite honestly this is not only the cleanest Dan Armstrong plexi bass I have owned, it also has a perfectly straight neck. I'm simply parting out my collection and don't have much use for the 30 1/2" scale length of this bass. Just look at the pictures to see the overall condition instead of listening to me rave on endlessly!"
"There is barely even a minor mark anywhere on the body & certainly do dings or gouges. There is some evidence the bass was played as shown by the wear on the back of the neck. The fretboard and frets are in near-perfect condition. It's a 24-fret neck bolt-on maple neck with rosewood fretboard. The pickup shows some of the typical bakelite flaking that all of these basses are known for; I have never seen a pickup that was in perfect condition. The pot dates are 36th week of 1970 and the serial number is D1458A. The bass weighs a very reasonable 10 lbs on the nose."
"The original case is as clean as the bass. Perfect interior, all the latches and the handle are in great shape and the tolex looks great. There is only some wear & tear on the leather ends. I am offering FREE WORLDWIDE SHIPPING on Saturday and Sunday only! After that, worldwide shipping will be $125 but USA will still be FREE. 14-day return privilege if you are not happy."
"Keep in mind that the neck is perfect but the bridge design and neck angle only allow for the bass to be set reasonably (yet very comfortably) low. This is a great bass for finger or pick styles but do NOT expect to use it for slap, pop & tap styles to any great degree."