This has been kicked around a few times back in the yellow forum days regarding the 124 Jnc the 127 never came up as I remember. As to date 127 Jnc I know of two possibly three and now yours, certainly appears to be quite rare. On the other hand 124's not as rare as once thought, seems to exist between (+/-) 16K to 19K numbered serial numbers, once again if memory serves me right.
Enjoy that that 127 as you do have a rare bird!
Cheers