The old molds were made I believe primarily for the Mustad and Eagle claw jig hooks. You should be able to use the sickle hooks but a problem that happens even in the Do-It molds is the length of the leg from the eyelet to the 90 degree bend - some of the sickles aren't uniform and some are longer than others. It has gotten better but if you use them you might run into it. Some of the guys have elongated the eyelet hole to get past this - but if you have to be careful if you do.

Here's an example of this - 4 of the same size hook and 4 different lengths from eyelet to 90 degree bend


I haven't found this so far in the Black Chrome sickles.