C.D. Buck A Dictionary of Selected Synonyms in the Principal Indo-European Languages reports 1016 results in 992 articles in BDAG alone. This resource gives solid coverage of this topic for us.
A modern alternative is Calvert Watkins The American Heritage Dictionary of Indo-European Roots. I recommend this work to supplement Buck's work.
I've started Book Suggestion pages for these works: Buck and Watkins, respectively. Thanks, in advance for your attention and support.
https://suggestbooks.uservoice.com/forums/308269-book-suggestions/suggestions/31692595-a-dictionary-of-selected-synonyms-in-the-principal
https://suggestbooks.uservoice.com/forums/308269-book-suggestions/suggestions/31692961-the-american-heritage-dictionary-of-indo-european
