Could be made up out of the spare parts box.
Looks to be an early 066 red light (064 never had the red light)- but with some later parts added.
Has the wide alloy flywheel- wider recoil starter cover and elastostart rope/handle from much later saws and decomp engine cover from same.
Alloy air box and flat filter of the 064/early 066 type, master control switch being metal shaft with red cast over plastic is period correct- but I am not sure the semi transparent fuel tank is correct for era.
So, depending on how much is true to original and how much has been parts swapped- could be pretty much a mash together of any of the 1122 model saws and parts thereof. Or, it could still be an original 066 red light with a few newer genuine parts to keep it running.