Newsletter at 8K. Starting Sponsors, need Pricing help.

Greetings

I know there are many resources and sites, but I think I want to know the direct answer here. My question is directly to newsletter owneres here.

I have an audience built from past 4 years to 8k members on my newsletter, its int he tv showbiz industry.
Open rate is around 25% and click rate is ~1% +- 0.5%.

Sending 4 mails weekly .

Planning to start taking sponsors for in mail ad spots, so I wanted to ask what pricing would be a nice one.

What I've gotten from a few resources is that $80 - $100 is a good starting point for a month of ad spot placement in mail.

What do you guys think?