yeah they are fairly common lugs (I THINK) and a friend of mine has a later mistral with really ugly lugs and poor craftsmanship just overall not as pretty as mine but i know holdsworth owned a few of the big early names like butler and others that they bought out when the firms went under so im assuming the later model butlers (and others) look like a holdsworth just with a butler label
but if i had to guess i would say the first half 70s or earlier ive been told that style of drop out went out of favor by 73 for MOST companys, but that doesnt mean people wernt still using them
and water mounts can always be added id guess its a repaint since theres no decals
is there any kind of serial number?
certainly people on here that know a lot more than I