7801640 is the part number for universal joints.
For finding part numbers, the -34P TM has all. I use it on electronic version. Find the figure number from the index, it is broken down by group, this being figure 93. For a M1008, the UOC is 208 so make sure this UOC number is on the description column for the item. Universal joints are an item shared throughout all variants so these work for 1008, I009, 1010, 1028s and 1031.