Seems like the best answer is for the bitog'rs that have vast bolt stashes to visit the OP, inspect be area where the bolt is missing, post photos, have another 5 page discussion about suitable replacement. Although eljefino will be helpful, the bolt wont come from his stash because his stuff is too rusty. a side discussion will ensue about how professional mechanics are hacks and thieves, especially dealers, and that's why the bolt is missing. Once a replacement is determined from the bolt stash we need to discuss sealants for 3 pages. Then we need to discuss torquing procedures for 2 pages and torque wrenches for a page. At this point the another bitog'r will attempt to torque the original pan bolt with a Chinese made wrench, then someone else will not feel secure about the accuracy of that torque at which point another bitog'r should volunteer to go over there with a Snap-on torque wrench. That will cause a 3 page discussion on the fact that not everyone has the budget for top of the line tools, a few comments about German made tools, Canadian Tire, and Harbor Freight screwdrivers will be made.
At the end of this, The Critic will come over to the OP's house and correct the vehicle's paint...
After all of that, gr8gastby will have saved $8.22 and many bitog'rs will feel warm and fuzzy.