This Dan Armstrong is being offered by Mainly Art Vintage Modern Furniture with an asking price of $2,900. Seems to be in very nice condition and is said to include the OHSC.
"Incredible vintage Lucite bass guitar with rosewood 24 fret finger board, lighter bolt on maple wood neck, spun aluminum control knobs, chrome Grover tuning keys and faux rosewood pick guard and headstock. Used in the day and today by many punk and classic rockers it's the main on stage or just for fun eye catching guitar. Engraved "Ampeg Dan Armstrong" to the pick guard and serial number D1438A, production circa 1970-1971. Includes the original fitted guitar case in very good to fine condition."
"In excellent vintage condition with some very slight marks from use and cleaning, the removable pick up has a small crack in it but can be replaced. On a 1 to 10, ten being the best I would rate this item at 9 because of the pick up . . ."