For anchors I'm doing these https://www.aliexpress.com/item/1005004529261503.html screwing in a hexagon bolt 5mm in and then welding it around the thread. Threaded inserts m4 20mm, m6 25mm, m8 30mm, m10 35mm. Total length with a hexbolt 50mm for m4, 60mm for m6, 70mm for m8 and 80mm for m10. Cost is about $400 for a total of 300 inserts. Unless you can make them yourself, like in the picture attached.
The slides have english in them, but not everything is translated. What kind of a machine are you building?