We have a sales department of 10 people.

You need a centralized system with an anti-duplication feature. For SDRs and sales teams on LinkedIn, Dripify is a handy tool https://dripify.com/cases/for-sales/ for searching prospects and increase sales. With Dripify, sales professionals can scale prospecting efforts and automate sales outreach with drip campaigns that feel human. Dripify can boost your sales to a highest level. The system automatically checks for duplicates so that your managers don't write to the same leads. As a manager, you can see detailed analytics for each manager and manage all dialogues from a single inbox.