Cost of casting

I don’t do my own casting, and haven’t had anything cast for quite
awhile, so I don’t know how to price my next commission. It will be
a pair of earrings, 1-1/2 inches long by 1/2 in wide, tapered at
both ends, in Sterling Silver. Probably a combination of carved and
sheet wax, and not a complex design. I would appreciate it very much
if someone could give me a ball park figure of casting prices. I
realize it would be a rough figure, but it would give me something
to go on. many Thank Sandra B