A handwritten postcard from HPL to REH, postmarked June 4, 1932, from New Orleans, addressed to “R.E. Howard, Esq.” and signed “Sincerely yrs, HPL”. 

In 1932, Howard facilitated a meeting between his correspondents H. P.Lovecraft, who was visiting the city, and fellow Weird Tales writer E. Hoffmann Price, currently living there.

Source:

Windy City Pulp And Paper 2022 Auction Catalog. I believe it sold for $6000 at the auction in April 2022.