Nice, this is what you’re looking for then: (might need a different size though, obviously)

E-Z LOK - 903816-25 E-Z Lok Threaded Insert, Zinc, Hex-Flanged, 3/8"-16 Internal Threads, 25mm Length (Pack of 25) - For Soft Wood https://www.amazon.com/dp/B002WC8TVG/ref=cm_sw_r_cp_api_glt_i_P7NT23KERK355JJCR5JH?_encoding=UTF8&psc=1