I have a 1935 B.C. Wills catalog.

Custom Hot Stamps and generic inlaid chips were $7 per hundred.

Regular c&s were $10 per hundred. Knurled edged c&s were $12.50 per hundred

I'm sure chips with different inlays were more but I didn't see them mentioned/

With the above in mind, this has to be the most expensive check available at the time: