You have found yourself a Keeper here. As far as the serial number , made in Jan,1984. The 145 could be the number of bass made that month but not sure. A little sketchy on that. The knobs are not original, and would be extremely hard to find 3 of the originals. They were black ribbed plastic, smaller on the bottom rising up to about 15/16th on top,flat on top with a dot marker. The screws were probably black or zinc plated originally .if you use Copper top batteries and unplug the bass ,when not in use, they should last about a year, again depends on the amount of use. As far as replacing the pickups on these , people are nuts. Westone basses and guitars used high quality pups. There are guys on TB that buy brand new 1200.00 dollar basses and change the pups out ,doesn't make any sense to me. That is the reason they sound so good, and the aged wood and the great necks, I could go on and on. The toggles were originally black also. Page 7 on this thread has another of these and maybe you could pm this TBer for more info on the controls. Pics please. If you wNt a number let me know. Welcome to Westone.