I would use findings in the same metal as the earring - IOW, use
sterling clips. I have bought them from Stuller, Rio, and Indian
Be aware that they cost much more than a post or hook.
You need to recalculate your sale price and account for both the
additional cost of clip findings as well as the additional (although
slight) work to properly solder and assemble them.
Judy in Kansas, where we should have temps in the upper 60s -
perfect for some garden clean-up.